Assessment of renal quality with quantitative contrast-enhanced ultrasound (CEUS) for differentiating kidney histopathology before procurement.

Purpose: This study aimed to investigate the use of contrast-enhanced ultrasonography (CEUS) to assess the kidneys' quality before procurement. Methods: This prospective study included 74 donors and 148 recipients of kidneys. 119 kidneys underwent quantitative analysis. Before organ procurement, potential kidney donors underwent CEUS, though organ procurement involved a zero-point puncture biopsy. CEUS parameters of the renal cortex and medulla were evaluated, including rise time (RT), time to peak (TTP), the area under the curve (AUC), wash-in slope (WIS), peak intensity (PI), and mean transit time (MTT). Donors' kidneys were classified based on their pathological. Additionally, short-term clinical indicators of renal recipients were collected and analyzed to determine whether the patients had delayed recovery of renal allograft function. Results: This experiment included 148 cases of kidney information, divided into two groups based on the Remuzzi score of the kidneys. However, 29 kidneys were excluded from the quantitative analysis due to loss or low quality of CEUS images. Comparing the time-intensity curve (TIC) of renal cortical region of interest (ROI), we found that the group with lower pathological scores exhibited higher PI (P=0.002), AUC(P=0.003), and WIS (P=0.009). TIC comparison results for renal medulla ROI revealed that the group with lower pathological scores had higher PI (P=0.010), AUC (P=0.023), and WIS (P=0.024). Conclusions: This study highlighted the potential of CEUS as a non-invasive, safe, and real-time examination method that correlates with the Remuzzi score and renal pathology. Therefore, it can be used as a prospective preoperative non-invasive evaluation method for the donor's kidney.

Successful treatment of a kidney transplant patient with COVID-19 and late-onset Pneumocystis jirovecii pneumonia.

BACKGROUND: Solid transplant patients are susceptible to Pneumocystis jirovecii pneumonia (PJP). While the vast majority of PJP cases occur within the first 6 months after transplantation, very few PJP cases are seen beyond 1 year post-transplantation (late-onset PJP). PJP and coronavirus disease 2019 (COVID-19, caused by infection with SARS-CoV-2) share quite a few common clinical manifestations and imaging findings, making the diagnosis of PJP often underappreciated during the current COVID-19 pandemic. To date, only 1 case of kidney transplantation who developed COVID-19 and late-onset PJP has been reported, but this patient also suffered from many other infections and died from respiratory failure and multiple organ dysfunction syndrome. A successful treatment of kidney patients with COVID-19 and late-onset PJP has not been reported. CASE PRESENTATION: We present a case of a 55-year-old male kidney transplant patient with COVID-19 who also developed late-onset PJP. He received a combined treatment strategy, including specific anti-pneumocystis therapy, symptomatic supportive therapy, adjusted immunosuppressive therapy, and use of antiviral drugs/antibiotics, ending with a favorable outcome. CONCLUSIONS: This case highlights the importance of prompt and differential diagnosis of PJP in kidney transplant patients with SARS-CoV-2 infection. Further studies are required to clarify if kidney transplant patients with COVID-19 could be prone to develop late-onset PJP and how these patients should be treated.

A familial cluster, including a kidney transplant recipient, of Coronavirus Disease 2019 (COVID-19) in Wuhan, China.

In December 2019, an outbreak of COVID-19 occurred in Wuhan, China, and spread to the whole of China and to multiple countries worldwide. Unlike SARS and MERS, where secondary transmission mostly occurred in hospital settings, COVID-19 transmission occurs in large numbers within families. Herein we report three cases of a familial cluster with one family member being a kidney transplant recipient. The initial clinical symptoms of COVID-19 in these three patients were the same, but their progression was different. Based on the severity of clinical symptoms, chest computer tomography findings and SARS-Cov-2 RNA test results, we admitted the husband to the respiratory intensive care unit (RICU) and used a treatment consisting of immunosuppressant reduction/cessation and low dose methylprednisolone-based therapy, and his wife to the respiratory isolation ward. In contrast, the son received in-home isolation and home-based care. All three family members made a full recovery.

Management of transplant patients outside hospital during COVID-19 epidemic: A Chinese experience.

Coronavirus disease 2019 (COVID-19) pandemic poses an increasing challenge for transplant community. Aggressive management measures are conductive to improve compliance and to lower the risk of intra-hospital infection. In this Personal Viewpoint essay, we shared experiences about management strategies of transplant patients outside hospital amid the epidemic. With the aid of Cloud Clinic service and telemedicine care, transplant patients could be regularly followed up and get medical consultation online. Furthermore, personal health education and mental health assistance are enrolled in our practice.

Human MiR-4660 regulates the expression of alanine-glyoxylate aminotransferase and may be a biomarker for idiopathic oxalosis.

BACKGROUND: Dysfunction of oxalate synthesis can cause calcium oxalate stone disease and inherited primary hyperoxaluria (PH) disorders. PH type I (PH1) is one of the most severe hyperoxaluria disorders, which results in urolithiasis, nephrocalcinosis, and end-stage renal disease. Here, we sought to determine the role of microRNAs in regulating AGXT to contribute to the pathogenesis of mutation-negative idiopathic oxalosis. METHODS: We conducted bioinformatics to search for microRNAs binding to AGXT, and examined the expression of the highest hit (miR-4660) in serum samples of patients with oxalosis, liver tissue samples, and determined the correlation and regulation between the microRNA and AGXT in vitro. RESULTS: MiR-4660 expression was downregulated in patients with oxalosis compared with healthy controls (84.03 copies/µL vs 33.02 copies/µL, P < 0.0001). Moreover, miR-4660 epigenetically decreased the expression of AGT in human liver tissues (Rho = - 0543, P = 0.037). Overexpression of miR-4660 in HepG2 and L02 cell lines led to dysregulation of AGXT at both the mRNA (by 71% and 81%, respectively; P < 0.001) and protein (by 49% and 42%, respectively; P < 0.0001) levels. We confirmed the direct target site of miR-4660 binding to the 3'UTR of AGXT by a luciferase assay. CONCLUSION: MiR-4660 is probably a new biomarker for mutation-negative idiopathic oxalosis by regulating the post-transcription of AGXT, providing a potential treatment target of mutation-negative idiopathic oxalosis.

Long-term outcome and recurrence of hepatitis B virus following liver transplantation from hepatitis B surface antigen-positive donors in a Chinese population.

Due to the severe shortage of the donor pool in China, a large number of patients are waiting for a suitable liver, or even worse lose the opportunity of transplantation. Reasonable use of hepatitis B surface antigen-positive (HBsAg-positive) donors is one possible strategy to increase the donor pool but the long-term outcome in a Chinese population is unknown. To evaluate the safety of using of HBsAg-positive donor for liver transplantation, we set up a multicentric retrospective study from 1 January 2007 to 31 December 2012. A total of 8632 patients underwent liver transplantation during the period and 282 (2.97%) received a liver from a HBsAg-positive donor. A total of 259 cases in both the case and control groups were matched. The incidence of postoperative liver dysfunction, early-stage and long-term complications and the 1-, 3- and 5-year patient survival (78.92% vs 85.65%, 60.41% vs 69.14%, 58.08% vs 69.14%, respectively) showed no difference between the two groups (P value > 0.05). However, the 1-, 3- and 5-year HBV recurrence for patients received the HBsAg-positive donor was higher compared with controls (5.85% vs 1.97%, 11.63% vs 4.46%, 17.94% vs 4.46%, respectively, P value = 0.016). Our results showed the use of HBsAg-positive donors is feasible and postoperative antiviral therapy should be managed.

Treatment of a MyD88 inhibitor alleviates rejection and inflammation in xenotransplantation by inhibiting dendritic cells activation and trained immunity in macrophages.

BACKGROUND: Acute vascular rejection (AVR) and systemic inflammation in xenograft recipients (SIXR) negatively impact the xenografts survival, and novel immunosuppressants are required to improve survival outcomes. We previously reported that TJ-M2010-5, a myeloid differentiation factor 88 (MyD88) inhibitor, exerts excellent anti-rejection effects in allogeneic transplantation. The aim of the present study was to evaluate the efficacy of TJ-M2010-5 in preventing AVR and SIXR and to investigate whether combined treatment of TJ-M2010-5 with anti-CD154 antibody (MR1) could prolong xenograft survival furthermore. METHODS: A model involving heart transplantation from Sprague-Dawley rats to BALB/c mice was established in vivo, and the xenografts developed typical AVR. Bone marrow-derived dendritic cells and macrophages were cultured to study the underlying mechanisms induced by rat cardiomyocyte lysate stimulation in vitro. RESULTS: TJ-M2010-5 monotherapy prolonged xenograft survival, although combination treatment with MR1 further enhanced the anti-AVR and anti-SIXR effects with about 21 days graft survival, compared to monotherapy. TJ-M2010-5 reduced dendritic cell and macrophage activation induced by xenotransplantation, downregulated CD80/CD86 expression, suppressed B-cell activation and anti-donor antibody generation, reduced pro-inflammatory cytokine production and tissue factor expression, and attenuated epigenetic modifications underlying interleukin-6 and tumor necrosis factor-α production in macrophages by inhibiting nuclear factor kappa B nuclear translocation. CONCLUSIONS: TJ-M2010-5 attenuated AVR and SIXR and contributed to xenograft survival by inhibiting dendritic cell and macrophage activation. A dual-system inhibition strategy combining TJ-M2010-5 with anti-CD154 antibody achieved better results in xenotransplantation.

Value of blood lipid in predicting graft dysfunction after organ and tissue transplantation: A study of Mendelian randomization.

Background: While immunosuppressive regimens have improved outcomes in solid organ transplantation, non-immune factors have also been identified as contributors to graft prognosis. Age, gender, hormones, heredity, and other diseases have been recognized to affect organ transplantation. However, the causal relationship between blood lipids and graft dysfunction remains unverified in human clinical investigations. In this study, we employed two-sample Mendelian randomization (MR) to examine the causality between different types of blood lipids and graft dysfunction following organ and tissue transplantation. Methods: We conducted a two-sample MR study using available genome-wide association summary data from the online database MRBASE (http://app.mrbase.org/), which encompasses over 11 billion associations between genetic factors and health-related outcomes, enabling researchers to explore various potential determinants of poor health. The exposure factors included four types of blood lipids: high-density lipoprotein, low-density lipoprotein, cholesterol, and triglycerides. For each exposure factor, three databases were selected for analysis. The outcome factor was the failure and rejection of transplanted organs and tissues. All databases consisted of European population samples, without specific subgroups. The related studies were conducted between 2016 and 2022, and the "TwoSampleMR" R package was employed for variant selection. Results: A total of 13 sample groups were collected and analyzed. The results revealed a causal association between blood lipids and graft dysfunction following organ and tissue transplantation. Specifically, the two-sample MR analysis confirmed that low-density lipoprotein and cholesterol levels were significant risk factors for increased graft dysfunction risk after transplantation. Moreover, high-density lipoprotein potentially reduced the risk of allograft dysfunction, while triglycerides possibly elevated the risk. Conclusions: Our recent study provides the initial confirmation that blood lipids may initiate causal pathological processes leading to graft dysfunction after organ and tissue transplantation.

The functions of SET domain bifurcated histone lysine methyltransferase 1 (SETDB1) in biological process and disease.

Histone methyltransferase SETDB1 (SET domain bifurcated histone lysine methyltransferase 1, also known as ESET or KMT1E) is known to be involved in the deposition of the di- and tri-methyl marks on H3K9 (H3K9me2 and H3K9me3), which are associated with transcription repression. SETDB1 exerts an essential role in the silencing of endogenous retroviruses (ERVs) in embryonic stem cells (mESCs) by tri-methylating H3K9 (H3K9me3) and interacting with DNA methyltransferases (DNMTs). Additionally, SETDB1 is engaged in regulating multiple biological processes and diseases, such as ageing, tumors, and inflammatory bowel disease (IBD), by methylating both histones and non-histone proteins. In this review, we provide an overview of the complex biology of SETDB1, review the upstream regulatory mechanisms of SETDB1 and its partners, discuss the functions and molecular mechanisms of SETDB1 in cell fate determination and stem cell, as well as in tumors and other diseases. Finally, we discuss the current challenges and prospects of targeting SETDB1 for the treatment of different diseases, and we also suggest some future research directions in the field of SETDB1 research.

The Novel MyD88 Inhibitor TJ-M2010-5 Protects Against Hepatic Ischemia-reperfusion Injury by Suppressing Pyroptosis in Mice.

BACKGROUND: . With the development of medical technology and increased surgical experience, the number of patients receiving liver transplants has increased. However, restoration of liver function in patients is limited by the occurrence of hepatic ischemia-reperfusion injury (IRI). Previous studies have reported that the Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88) signaling pathway and pyroptosis play critical roles in the development of hepatic IRI. METHODS: . A mouse model of segmental (70%) warm hepatic IRI was established using BALB/c mice in vivo. The mechanism underlying inflammation in mouse models of hepatic IRI was explored in vitro using lipopolysaccharide- and ATP-treated bone marrow-derived macrophages. This in vitro inflammation model was used to simulate inflammation and pyroptosis in hepatic IRI. RESULTS: . We found that a MyD88 inhibitor conferred protection against partial warm hepatic IRI in mouse models by downregulating the TLR4/MyD88 signaling pathway. Moreover, TJ-M2010-5 (a novel MyD88 inhibitor, hereafter named TJ-5) reduced hepatic macrophage depletion and pyroptosis induction by hepatic IRI. TJ-5 treatment inhibited pyroptosis in bone marrow-derived macrophages by reducing the nuclear translocation of nuclear factor kappa-light-chain-enhancer of activated B cells, decreasing the release of high-mobility group box-1, and promoting endocytosis of lipopolysaccharide-high-mobility group box-1 complexes. CONCLUSIONS: . Inhibition of MyD88 may protect the liver from partial warm hepatic IRI by reducing pyroptosis in hepatic innate immune cells. These results reveal the mechanism underlying the development of inflammation in partially warm hepatic IRI and the induction of cell pyroptosis.

Values of Donor Serum Lipids and Calcium in Predicting Graft Function after Kidney Transplantation: A Retrospective Study.

OBJECTIVE: Delayed graft function (DGF) and early graft loss of renal grafts are determined by the quality of the kidneys from the deceased donor. As "non-traditional" risk factors, serum biomarkers of donors, such as lipids and electrolytes, have drawn increasing attention due to their effects on the postoperative outcomes of renal grafts. This study aimed to examine the value of these serum biomarkers for prediction of renal graft function. METHODS: The present study consecutively collected 306 patients who underwent their first single kidney transplantation (KT) from adult deceased donors in our center from January 1, 2018 to December 31, 2019. The correlation between postoperative outcomes [DGF and abnormal serum creatinine (SCr) after 6 and 12 months] and risk factors of donors, including gender, age, body mass index (BMI), past histories, serum lipid biomarkers [cholesterol, triglyceride, high-density lipoprotein (HDL) and low-density lipoprotein (DL)], and serum electrolytes (calcium and sodium) were analyzed and evaluated. RESULTS: (1) Donor age and pre-existing hypertension were significantly correlated with the incidence rate of DGF and high SCr level (≥2 mg/dL) at 6 and 12 months after KT (P<0.05); (2) The donor's BMI was significantly correlated with the incidence rate of DGF after KT (P<0.05); (3) For serum lipids, merely the low level of serum HDL of the donor was correlated with the reduced incidence rate of high SCr level at 12 months after KT [P<0.05, OR (95% CI): 0.425 (0.202-0.97)]; (4) The serum calcium of the donor was associated with the reduced incidence rate of high SCr level at 6 and 12 months after KT [P<0.05, OR (95% CI): 0.184 (0.045-0.747) and P<0.05, OR (95% CI): 0.114 (0.014-0.948), respectively]. CONCLUSION: The serum HDL and calcium of the donor may serve as predictive factors for the postoperative outcomes of renal grafts after KT, in addition to the donor's age, BMI and pre-existing hypertension.

New Insights into the Functions of MicroRNAs in Cardiac Fibrosis: From Mechanisms to Therapeutic Strategies.

Cardiac fibrosis is a significant global health problem associated with almost all types of heart disease. Extensive cardiac fibrosis reduces tissue compliance and contributes to adverse outcomes, such as cardiomyocyte hypertrophy, cardiomyocyte apoptosis, and even heart failure. It is mainly associated with pathological myocardial remodeling, characterized by the excessive deposition of extracellular matrix (ECM) proteins in cardiac parenchymal tissues. In recent years, a growing body of evidence demonstrated that microRNAs (miRNAs) have a crucial role in the pathological development of cardiac fibrosis. More than sixty miRNAs have been associated with the progression of cardiac fibrosis. In this review, we summarized potential miRNAs and miRNAs-related regulatory mechanisms for cardiac fibrosis and discussed the potential clinical application of miRNAs in cardiac fibrosis.

TJ-M2010-5, A self-developed MyD88 inhibitor, attenuates liver fibrosis by inhibiting the NF-κB pathway.

Liver fibrosis is the result of most chronic inflammatory liver damage and seriously endangers human health. However, no drugs have been approved to treat this disease. Previous studies showed that the Toll-like receptors (TLRs)/myeloid differentiation factor-88 (MyD88)/nuclear factor-κB (NF-κB) pathway plays a key role in liver fibrosis. TJ-M2010-5 is a self-developed small molecule MyD88 inhibitor, which has been proven to have a good protective effect in a variety of inflammatory disease models. In the present study, to investigate the anti-fibrotic effect of TJ-M2010-5, mice were injected with carbon tetrachloride (CCl4) in vivo and LX2 cells (a human hepatic stellate cell line) were treated with TGF-ß1 in vitro to induce liver fibrosis. In vivo studies showed that TJ-M2010-5 attenuated the CCl4-induced liver damage, collagen accumulation, and the activation of hepatic stellate cells by inhibiting the nuclear transfer of NF-κB. Moreover, in vitro experiments of LX2 cells stimulated with TGF-ß1 further indicated that the NF-κB pathway is involved in the development of liver fibrosis. TJ-M2010-5 significantly inhibited the proliferation and activation of LX2 cells. In addition, TJ-M2010-5 upregulated the expression of bone morphogenetic protein and membrane-bound inhibitor (BAMBI) in LX2 cells by blocking the activation of MyD88/NF-κB, thereby inhibiting the phosphorylation of Smad2/3 and the expression of collagen I (COL1A1) induced by TGF-ß1. In conclusion, this study illustrates the anti-hepatic fibrosis effect of TJ-M2010-5 and provides a new treatment method for liver fibrosis.

Infective Artery Rupture of Renal Allografts: A Single-Center Retrospective Study in China.

OBJECTIVE: This study investigated the composition of pathogenic microorganisms, clinical features, and therapeutic strategies of infective artery rupture of renal allografts in recipients receiving deceased donor (DD) kidneys. METHODS: We retrospectively studied the clinical data of the DD kidney transplant recipients with donor-associated infection at Tongji Hospital, Wuhan, China from January 1, 2015 to December 31, 2018, related recipients and corresponding donors. We collected the entire results of pathogenic microorganisms cultured from these related ruptured kidneys and then analyzed their distribution and differences. RESULTS: A total of 1440 kidney transplants from DD were performed in our center. The total incidence of infective artery rupture in kidney transplants was about 0.76% (11/1440), and the annual incidence ranged from 0.25% to 1.03%. The microbial culture results revealed that 11 recipients suffered from infective artery rupture and 3 recipients who accepted the kidney from same donor had the donor-associated pathogens, including 9 fungal strains (28.1%) and 23 bacterial strains (71.9%). There were 4 recipients infected with multi-drug-resistant Staphylococcus and Klebsiella pneumoniae from the above 11 recipients, of which, 10 recipients underwent graft loss, and one died of septic shock. The microbial cultures of the remaining 3 recipients who received appropriate anti-infective regimens turned negative eventually, and the patients were discharged successfully without significant complications. CONCLUSION: Renal recipients with infections derived from DDs were at high risk of artery rupture, graft loss, or even death. Appropriate anti-infective treatment is essential to reduce the incidence of artery rupture and mortality.

TJ-M2010-5, a novel CNS drug candidate, attenuates acute cerebral ischemia-reperfusion injury through the MyD88/NF-κB and ERK pathway.

Background: Cerebral ischemia-reperfusion injury (CIRI) inevitably occurs after vascular recanalization treatment for ischemic stroke. The accompanying inflammatory cascades have a major impact on outcome and regeneration after ischemic stroke. Evidences have demonstrated that TLR/MyD88/NF-κB signaling contributes to CIRI. This study aimed to investigate the druggability of MyD88 in the central nervous system (CNS) and the neuroprotective and anti-neuroinflammatory effects of the MyD88 inhibitor TJ-M2010-5 on CIRI. Methods: A middle cerebral artery occlusion (MCAO) model was used to simulate CIRI in mice. BV-2 cells were stimulated with oxygen glucose deprivation/reoxygenation (OGD/R) or lipopolysaccharide, and SH-SY5Y cells were induced by OGD/R in vitro. Neurological deficit scores and cerebral infarction volumes were evaluated. Immunofluorescence staining was performed to measure neuronal damage and apoptosis in the brain. The anti-neuroinflammatory effect of TJ-M2010-5 was evaluated by analyzing the expression of inflammatory cytokines, activation of microglia, and infiltration of peripheral myeloid cells. The expression of proteins of the MyD88/NF-κB and ERK pathway was detected by Simple Western. The concentrations of TJ-M2010-5 in the blood and brain were analyzed by liquid chromatography-mass spectrometry. Results: The cerebral infarction volume decreased in mice treated with TJ-M2010-5, with the most prominent decrease being approximately 80% of the original infarction volume. Neuronal loss and apoptosis were reduced following TJ-M2010-5 treatment. TJ-M2010-5 inhibited the infiltration of peripheral myeloid cells and the activation of microglia. TJ-M2010-5 also downregulated the expression of inflammatory cytokines and inhibited the MyD88/NF-κB and ERK pathway. Furthermore, TJ-M2010-5 showed good blood-brain barrier permeability and no neurotoxicity. Conclusion: TJ-M2010-5 has an excellent therapeutic effect on CIRI as a novel CNS drug candidate by inhibiting excessive neuroinflammatory responses.

[Histopathologic analysis of 1500 renal allograft biopsies].

OBJECTIVE: To summarize the histopathological features of posttransplant complications for renal allografts and evaluate the biopsy values. METHODS: Between January 1997 and May 2010, a total of 1712 percutaneous renal allograft biopsies were performed in 1500 kidney transplants and diagnostic procedures for staining, classification and staging had been performed according to the Banff 1997 and 2005 Schema. RESULTS: There were 213 (14.2%) cases of acute T cell-mediated rejection post transplantation in 1500 kidney transplants. Meanwhile there were 36 (2.4%) cases of acute antibody-mediated rejection. Chronic T cell-mediated rejection and chronic antibody-mediated rejection were 251 (16.7%) cases and 45 (3.0%) cases, respectively. Acute CNI-nephrotoxicity and chronic CNI-nephrotoxicity were 106 (7.1%)cases and 251 (16.7%) cases, respectively. Relapsed or new nephropathy were 6 (0.4%) cases. Chronic CNI-nephrotoxicity is the most common cause of allograft dysfunction in the long survival recipients. CONCLUSION: Percutaneous renal allograft biopsy is valuable for the diagnosis of various posttransplantation complications.

[Histopathological study of 268 hepatic allograft biopsies].

OBJECTIVE: To observe the histopathological features of posttransplant complications for hepatic allografts and evaluate their biopsy values. METHODS: From January 1999 to May 2011, a total of 268 percutaneous hepatic allograft biopsies were conducted in 207 recipients and the diagnostic procedures for staining, classification and staging performed according to the Banff schema and Chinese Schema on hepatic allograft rejection. RESULTS: Among them, there were ischemia/reperfusion injury (n = 26, 9.7%), acute T cell-mediated rejection (n = 83, 31.0%), acute antibody-mediated rejection (n = 12, 4.5%), chronic posttransplantation rejection (n = 31, 11.6%), immunosuppressive-induced liver injury (n = 70, 26.1%) and recurrent diseases (n = 18, 6.7%). Acute T cell-mediated rejection and drug-induced liver injury were two most common causes of allograft dysfunctions. CONCLUSION: Percutaneous hepatic allograft biopsy is valuable for the diagnosis and evaluation of various posttransplantation complications.

Kidney stone disease and cardiovascular events: a study on bidirectional causality based on mendelian randomization.

BACKGROUND: Kidney stone disease (KSD) has been reported to be associated with several cardiovascular diseases. However, the causality between the conditions remains unknown. In the study, we performed a study on bidirectional causality by two-sample Mendelian randomization (MR) to investigate the causality between KSD and cardiovascular diseases including coronary atherosclerosis, hypertension, and cardiomyopathy. METHODS: In the recent study, we performed a bidirectional two-sample MR study using available genome-wide association summary data from the online database MRBASE. We identified genetic variants associated with KSD in one European population from UK Biobank (version 2, n=462,933). Two phenotypes of samples were chosen from the population to define our genetic instrumental variables: (I) samples with the phenotype of kidney stone/ureter stone/bladder stone (ukb-b-8297), and (II) samples with the phenotype of kidney stone surgery/lithotripsy (ukb-b-13537). For cardiovascular diseases, we picked up another independent European population from FinnGen Biobank (n=93,421). We selected the exposure and outcome SNPs and then performed the two-sample MR using R package. RESULTS: After bidirectional causality by two-sample MR, we verified that genetic predisposition to KSD could increase the risk of coronary atherosclerosis (OR: 4.45×1037; SE=±7.80×1014, P for MR-Egger =0.024) and cardiomyopathy (OR: 5.35×1013; SE=±7.18×106, P for IVW=0.045 for finn-a-I9_CARDMYO, and OR: 3.60×1025; SE=±3.26×1012, P for IVW=0.041 for finn-a-I9_CARDMYOOTH) when we used ukb-b-13537 as exposure group. Furthermore, hypertension could increase the risk of KSD (OR: 1.001; SE=±1.00, P for IVW=0.003) when we used ukb-b-8297 as exposure group, without detected pleiotropy bias (P>0.05). CONCLUSIONS: We confirmed KSD may trigger causal pathological processes including coronary atherosclerosis and cardiomyopathy. Furthermore, hypertension may causally affect KSD.

miR-190a-5p Partially Represses the Abnormal Electrical Activity of SCN3B in Cardiac Arrhythmias by Downregulation of IL-2.

Cardiac arrhythmias (CAs) are generally caused by disruption of the cardiac conduction system; interleukin-2 (IL-2) is a key player in the pathological process of CAs. This study aimed to investigate the molecular mechanism underlying the regulation of IL-2 and the sodium channel current of sodium voltage-gated channel beta subunit 3 (SCN3B) by miR-190a-5p in the progression of CAs. ELISA results suggested the concentration of peripheral blood serum IL-2 in patients with atrial fibrillation (AF) to be increased compared to that in normal controls; fluorescence in situ hybridization indicated that the expression of IL-2 in the cardiac tissues of patients with AF to be upregulated and that miR-190a-5p to be downregulated. Luciferase reporter assay, quantitative real-time-PCR, and whole-cell patch-clamp experiments confirmed the downregulation of IL-2 by miR-190a-5p and influence of the latter on the sodium current of SCN3B. Overall, miR-190a-5p suppressed the increase in SCN3B sodium current caused by endogenous IL-2, whereas miR-190a-5p inhibitor significantly reversed this effect. IL-2 was demonstrated to be directly regulated by miR-190a-5p. We, therefore, concluded that the miR-190a-5p/IL-2/SCN3B pathway could be involved in the pathogenesis of CAs and miR-190a-5p might acts as a potential protective factor in pathogenesis of CAs.