Optimal assessment of the glomerular filtration rate in older chinese patients using the equations of the Berlin Initiative Study.

AIM: To evaluate the performances of the various estimated glomerular filtration rate (eGFR) equations of the Chronic Kidney Disease Epidemiology Collaboration, the Berlin Initiative Study (BIS), and the Full Age Spectrum (FAS) in older Chinese. METHODS: This study enrolled Chinese adults aged ≥ 65 years who underwent GFR measurements (via 99Tcm-DTPA renal dynamic imaging) in our hospital from 2011 to 2022. Using the measured glomerular filtration rate (mGFR) as the reference, we derived the bias, precision, accuracy, and consistency of each equation. RESULTS: We enrolled 519 participants, comprising 155 with mGFR ≥ 60 mL/min/1.73 m2 and 364 with mGFR < 60 mL/min/1.73 m2. In the total patients, the BIS equation based on creatinine and cystatin C (BIScr-cys) exhibited the lowest bias [median (95% confidence interval): 1.61 (0.77-2.18)], highest precision [interquartile range 11.82 (10.32-13.70)], highest accuracy (P30: 81.12%), and best consistency (95% limit of agreement: 101.5 mL/min/1.73 m2). In the mGFR ≥ 60 mL/min/1.73 m2 subgroup, the BIScr-cys and FAS equation based on creatinine and cystatin C (FAScr-cys) performed better than the other equations; in the mGFR < 60 mL/min/1.73 m2 subgroup, all equations exhibited relatively large deviations from the mGFR. Of all eight equations, the BIScr-cys performed the best. CONCLUSIONS: Although no equation was fully accurate in the mGFR < 60 mL/min/1.73 m2 subgroup, the BIScr-cys (of the eight equations) assessed the eGFRs of the entire population best. A new equation is urgently required for older Chinese and even East Asians, especially those with moderate-to-severe renal insufficiency.

Clinical characteristics of membranous nephropathy with spontaneous remission: An analysis of 24 patients / Características clínicas de la nefropatía membranosa con remisión espontánea: análisis de 24 pacientes

Purpose To investigate the prognosis of patients with spontaneous remission (SR) of phospholipase A2 receptor (PLA2R)-associated membranous nephropathy (MN).Patients and methods Patients diagnosed with MN were recruited after examining their renal biopsy in the Renal Department of China-Japan Friendship Hospital between January 2015 and September 2021. Among them, 24 patients with SR were included in this study and follow-up. Results Twenty-four patients diagnosed with SR of PLA2R-associated MN were recruited; 11 were male, and 13 were female, with a mean age of 49.5±14.5 years (range, 30–77 years). The initial 24-hour urinary total protein and serum albumin levels were 0.29±0.14g/d and 37.5±4.4g/L, respectively, and the initial serum creatinine was 65.0±15.8μmol/L. During the follow-up of 33.9±19.1 months (range, 6–73 months), 22 (91.7%) patients maintained remission; however, one patient had impaired renal function due to acute coronary syndrome and coronary angiography findings, and one patient experienced a repeated relapse caused by respiratory tract infection, at 50 and 70 months. A systematic review of the relevant literature was conducted, and records of patients with SR of PLA2R-associated MN were retrieved from 16 case reports or case series with a total of 97 cases. ConclusionsMost patients with SR of MN had a promising long-term prognosis, with only a few cases of relapse. (AU)

Objetivo Investigar el pronóstico de los pacientes con remisión espontánea en la nefropatía membranosa (MN, por sus siglas en inglés) asociada al receptor fosfolipasa A2 (PLA2R). Pacientes y métodos Pacientes con MN diagnosticados por biopsia renal en el Departamento Renal del China-Japan Friendship Hospital entre enero de 2015 y septiembre de 2021. Entre ellos, 24 pacientes con remisión espontánea fueron reclutados y seguidos. Resultados Se reclutaron 24 pacientes con MN en remisión espontánea asociada a PLA2R; 11 varones y 13 mujeres, con una edad media de 49,5±14,5 años (rango: 30-77 años) en el momento del diagnóstico. La proteína total y la albúmina sérica en orina de 24h iniciales fueron de 0,29±0,14 y 37,5±4,4g/l, respectivamente; la creatinina sérica inicial fue de 65,0±15,8μmol/l. Durante el seguimiento de 33,9±19,1 (rango: 6-73) meses, 22 pacientes (91,7%) mantienen la remisión. Un paciente presentó insuficiencia renal por síndrome coronario agudo y angiografía coronaria. Otro paciente tuvo una recaída causada por una infección del tracto respiratorio 2 veces, a los 50 y 70 meses. Se realizó una revisión sistemática de la literatura. Los pacientes con MN asociada con PLA2R en remisión espontánea se recuperaron en 16 informes o series de casos, de 97 casos en total. ConclusionesLa mayoría de los pacientes con MN en remisión espontánea tuvieron un pronóstico prometedor a largo plazo, mientras que solo unos pocos casos tuvieron recaída. (AU)

Clinical characteristics of membranous nephropathy with spontaneous remission: An analysis of 24 patients.

PURPOSE: To investigate the prognosis of patients with spontaneous remission (SR) of phospholipase A2 receptor (PLA2R)-associated membranous nephropathy (MN). PATIENTS AND METHODS: Patients diagnosed with MN were recruited after examining their renal biopsy in the Renal Department of China-Japan Friendship Hospital between January 2015 and September 2021. Among them, 24 patients with SR were included in this study and follow-up. RESULTS: Twenty-four patients diagnosed with SR of PLA2R-associated MN were recruited; 11 were male, and 13 were female, with a mean age of 49.5±14.5 years (range, 30-77 years). The initial 24-hour urinary total protein and serum albumin levels were 0.29±0.14g/d and 37.5±4.4g/L, respectively, and the initial serum creatinine was 65.0±15.8µmol/L. During the follow-up of 33.9±19.1 months (range, 6-73 months), 22 (91.7%) patients maintained remission; however, one patient had impaired renal function due to acute coronary syndrome and coronary angiography findings, and one patient experienced a repeated relapse caused by respiratory tract infection, at 50 and 70 months. A systematic review of the relevant literature was conducted, and records of patients with SR of PLA2R-associated MN were retrieved from 16 case reports or case series with a total of 97 cases. CONCLUSIONS: Most patients with SR of MN had a promising long-term prognosis, with only a few cases of relapse.

Pyroptosis: A New Frontier in Kidney Diseases.

Pyroptosis is a pattern of programmed cell death that significantly differs from apoptosis and autophagy in terms of cell morphology and function. The process of pyroptosis is characterized predominantly by the formation of gasdermin protein family-mediated membrane perforation, cell collapse, and the release of inflammatory factors, including IL-1ß and IL-18. In recent years, with the rise of pyroptosis research, scholars have devoted time to study the mechanism of pyroptosis in kidney-related diseases. Pyroptosis is probably involved in kidney diseases through two pathways: the caspase-1-mediated canonical pathway and the caspase-4/5/11-mediated noncanonical pathway. In addition, some scholars have identified targets for the treatment of kidney-related diseases from the viewpoint of pyroptosis and developed corresponding medicines, which may become a recommendation for prognosis, targeted treatment, and clinical diagnosis of kidney diseases. This paper focuses on the up-to-date advances in the field of pyroptosis, especially on the key pathogenic role of pyroptosis in the development and progression of kidney diseases. It presents a more in-depth understanding of the pathogenesis of kidney diseases and introduces novel therapeutic targets for the prevention and clinical treatment of kidney diseases.

Efficacy and Safety of a Combination of Shenmai Injection plus Chemotherapy for the Treatment of Lung Cancer: A Meta-Analysis.

OBJECTIVE: To perform a systematic evaluation of the efficacy and safety of combined treatment of Shenmai injection and chemotherapy for lung cancer. METHODS: A literature search for randomized controlled trials (RCTs) describing the treatment of lung cancer by Shenmai injection and chemotherapy or chemotherapy alone was performed using the PubMed, Cochrane Library, China National Knowledge Infrastructure (CNKI), Value In Paper (VIP), China BioMed, and Wanfang databases. The databases were searched for entries published before September 1, 2019. RESULTS: Thirty-seven RCTs, comprising a total of 2808 cases, were included in the present meta-analysis. Of these, 1428 cases were treated by Shenmai injection plus chemotherapy, and 1380 cases were treated only by chemotherapy. The results of meta-analysis showed that the combined treatment (Shenmai injection plus chemotherapy) increased the short-term efficacy of treatment (relative risk [RR] = 1.183, 95% confidence interval [CI] = 1.043-1.343, P < 0.01) and improved patients' quality of life (RR = 1.514, 95%CI = 1.211-1.891, P < 0.01) compared with chemotherapy alone. With regard to the adverse effects, the combined treatment markedly reduced the incidence of white blood cell (WBC) reduction (RR = 0.846, 95%CI = 0.760-0.941, P < 0.01), platelet reduction (RR = 0.462, 95% CI = 0.330-0.649, P < 0.01), and hemoglobin reduction (RR = 0.462, 95% CI = 0.330-0.649, P < 0.01) and alleviated drug-induced liver injury (RR = 0.677, 95%CI = 0.463-0.990, P < 0.05). However, it did not offer a significant protective effect (RR = 0.725, 95%CI = 0.358-1.468, P < 0.05). The effect of the combined treatment on the occurrence of vomiting was considerable (RR = 0.889, 95%CI = 0.794-0.996, P < 0.05), and the combined treatment markedly increased the immunity of patients with lung cancer. CONCLUSION: The combined treatment of Shenmai injection plus chemotherapy enhanced the short-term efficacy of chemotherapy, improved the patient quality of life, alleviated the adverse effects of chemotherapeutics, and increased the patient immunity. These results should be confirmed by large-scale, high-quality RCTs.

p53: A Key Protein That Regulates Pulmonary Fibrosis.

Pulmonary fibrosis is a progressively aggravating lethal disease that is a serious public health concern. Although the incidence of this disease is increasing, there is a lack of effective therapies. In recent years, the pathogenesis of pulmonary fibrosis has become a research hotspot. p53 is a tumor suppressor gene with crucial roles in cell cycle, apoptosis, tumorigenesis, and malignant transformation. Previous studies on p53 have predominantly focused on its role in neoplastic disease. Following in-depth investigation, several studies have linked it to pulmonary fibrosis. This review covers the association between p53 and pulmonary fibrosis, with the aim of providing novel ideas to improve the clinical diagnosis, treatment, and prognosis of pulmonary fibrosis.

A Clinical Model for the Prediction of Acute Exacerbation Risk in Patients with Idiopathic Pulmonary Fibrosis.

OBJECTIVE: To develop and validate a risk assessment model for the prediction of the acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) in patients with idiopathic pulmonary fibrosis (IPF). METHODS: We enrolled a total of 110 patients with IPF, hospitalized or treated as outpatients at Xuzhou Traditional Chinese Medicine Hospital Affiliated to Nanjing University of Chinese Medicine from July 2012 to July 2020. Of these, 78 and 32 patients were randomly assigned to training and test groups, respectively. The risk factors for AE-IPF were analyzed using logistic regression analysis, and a nomographic model was constructed. The accuracy, degree of calibration, and clinical usefulness of the model were assessed with the consistency index (C-index), calibration diagram, and decision curve analysis (DCA). Finally, the stability of the model was tested using internal validation. RESULTS: The results of logistic regression analysis showed that a history of occupational exposure, diabetes mellitus (DM), essential hypertension (EH), and diffusion capacity for carbon monoxide (DLCO)% predicted were independent risk factors for AE-IPF prediction. The nomographic model was constructed based on these independent risk factors, and the C-index was 0.80. The C-index for the internal validation was 0.75, suggesting that the model had good accuracy. The decision curve indicated that for a threshold value of 0.04-0.66, greater clinical benefit was obtained with the AE-IPF risk prediction model. CONCLUSION: A customized AE-IPF prediction model based on a history of occupational exposure, DM, EH, and DLCO% predicted provided a reference for the clinical prediction of AE-IPF.

Angiotensin II type 1 receptor blockers favorably affect renal angiotensin II and MAS receptor expression in patients with diabetic nephropathy.

INTRODUCTION: The aims of this study were to assess the renal expression of angiotensin II type 1 receptor (AT1R), angiotensin II type 2 receptor (AT2R), and MAS receptor in human type 2 diabetic nephropathy (DN). MATERIALS AND METHODS: In total, 115 patients diagnosed with DN by renal biopsy were enrolled in this study. The protein expression levels of the AT1R, AT2R, and MAS receptors were assessed by immunohistochemistry. RESULTS: The protein expression levels of AT1R, AT2R, and MAS receptor in the renal biopsy tissue were correlated with the pathologic classification of DN. Tubulointerstitial AT1R expression in patients of class IIb was significantly stronger than control samples (p < 0.05). Expression of AT2R and MAS receptors were highest with class IIb DN patients. When DN patients were treated with AT1R blocker (ARB), the expression of AT1R was downregulated (p < 0.05), and the MAS receptor was upregulated in tubular interstitial (p < 0.05). CONCLUSIONS: Our results directly observed that renal expression levels of AT1R increase during the early stages of DN, ARB reducing AT1R while increasing MAS receptor. Therefore, ARB should be used as soon as possible in patients with DN.

Efficacy and Safety of Tanshinone for Chronic Kidney Disease: A Meta-Analysis.

OBJECTIVE: To systematically evaluate the efficacy and safety of tanshinone for chronic kidney disease (CKD). METHODS: Randomized controlled trials (RCTs) on the treatment of CKD using tanshinone were searched using 4 Chinese databases (China National Knowledge Infrastructure (CNKI), Value In Paper (VIP), Wanfang, and Chinese Biology Medicine (CBM)) and 3 English databases (PubMed, Cochrane Library, and Excerpta Medica Database (Embase)). The results included data on blood urine nitrogen (BUN), serum creatinine (Scr), glomerular filtration rate (GFR), 24 h urine protein, microalbuminuria (mALB), ß2-macroglobulin (ß2-MG), cystatin C (CysC), and safety events. The data were analyzed using Revman 5.3 and Stata 12.0 software. RESULTS: Twenty-one studies were entered into this meta-analysis, which involved 1857 patients including 954 cases from the tanshinone treatment group and 903 cases from the control group. BUN levels in the tanshinone treatment group were significantly reduced compared with the control (standardized mean difference (SMD) = -0.65, 95% confidence interval (CI): -0.81 to -0.49, p < 0.01). In addition, subgroup analysis indicated that tanshinone had a significant effect in reducing Scr levels at 14, 21, and 28 days. Scr levels in the tanshinone treatment group were significantly reduced compared with the control group (SMD = -1.40, 95% CI: -2.09 to -0.71, p < 0.01); subgroup analysis based on treatment time also yielded the same results. GFR in the tanshinone treatment group was better than that in the control group (SMD = 0.83, 95% CI: 0.59 to 1.07, p < 0.01). In terms of urine protein levels, 24 h urine protein level, mALB, and ß2-MG of CKD patients were reduced to some degree compared with controls, and CysC levels in the tanshinone treatment group were also significantly reduced compared with the control group (SMD = -0.24, 95% CI: -0.44 to -0.03, p < 0.05). Safety in the tanshinone treatment group did not differ significantly from that of the control group (risk ratio (RR) = 7.78, 95% CI: 0.99 to 61.05, p > 0.05). CONCLUSION: This meta-analysis showed that tanshinone could control urine protein level in CKD patients, improve kidney function, and delay the evolution of CKD without significant side effects. However, the results were limited and should be interpreted with caution because of the low quality of the included studies. In the future, more rigorous clinical trials need to be conducted to provide sufficient and accurate evidence.

Effects of adding tripterygium glycosides to angiotensin-converting enzyme inhibitors or angiotensin receptor blockers on albuminuria in patients with diabetic nephropathy.

INTRODUCTION: Tripterygium glycosides (TGs) have been widely used in China to treat diabetic nephropathy (DN); however, proof of their use is scarce. The present study aimed to evaluate the effectiveness and safety of adding TGs to angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs). METHODS: By searching Embase, MEDLINE, Cochrane Library, SINOMED, China National Knowledge Infrastructure, VIP Information/Chinese Scientific Journals, and WANFANG databases, we identified previous studies that met the specific selection criteria and included them in the meta-analysis. Analyses were performed using Review Manager (version 5.3). RESULTS: Nine randomized controlled trials were included in the final meta-analysis. Patients were compared before and after treatment with ACE inhibitors or ARBs plus TGs, or ACE inhibitors or ARBs alone. The results revealed that treatment with ACE inhibitors or ARBs plus TGs resulted in significantly greater reductions in 24-h urinary total protein (UTP) levels (trial duration <2 months, mean difference [MD]: -0.25; 95% confidence interval [CI]: -0.32, -0.18; trial duration between 2 and 6 months, MD: -0.39; 95% CI: -0.44, -0.33; trial duration >6 months, MD: -2.09; 95% CI: -2.89, -1.29) compared with treatment using ACE inhibitors or ARBs alone. Additionally, ACE inhibitors or ARBs plus TGs showed better results after long-term administration. Treatment with ACE inhibitors or ARBs plus TGs resulted in significantly greater reductions in serum creatinine (SCr) compared with ACE inhibitors or ARBs alone (MD: -9.87; 95% CI: -13.76, -5.97). CONCLUSION: In patients with DN, adding TGs to ACE inhibitors or ARBs significantly lowered both the 24-h UTP and SCr levels. Therefore, ACE inhibitors or ARBs plus TGs might improve the treatment of DN in patients.

Efficacy and safety of immunosuppressive treatment in IgA nephropathy: a meta-analysis of randomized controlled trials.

BACKGROUND: Immunosuppressive agents have been widely used in the treatment of IgA nephropathy (IgAN), but the efficacy and safety remain controversial. The recent STOP-IgAN and TESTING studies have again focused attention on the application of immunosuppressive agents in IgAN. This study investigated the benefits and risks of immunosuppressive agents in IgAN. METHODS: MEDLINE, EMBASE, the Cochrane Library, and article reference lists were searched for randomized controlled trials (RCTs) comparing immunosuppressive agents with any other non-immunosuppressive agents for treating IgAN. A meta-analysis was performed on the outcomes of proteinuria, creatinine (Cr), estimated glomerular filtration rate (eGFR), and adverse events in patients with IgAN, and trial sequential analyses were also performed for outcomes. RESULTS: Twenty-nine RCTs (1957 patients) that met our inclusion criteria were identified. Steroids (weighted mean difference [WMD] -0.70, 95% confidence interval [CI] -1.2 to - 0.20), non-steroidal immunosuppressive agents (NSI) (WMD -0. 43, 95% CI - 0.55 to - 0.31), and combined steroidal and non-steroidal immunosuppressive agents (S&NSI) (WMD -1.46, 95% CI - 2.13 to - 0.79) therapy significantly reduced proteinuria levels compared with the the control group. Steroid treatment significantly reduced the risk of end-stage renal disease (ESRD) (relative risk [RR] 0.39, CI 0.19 to 0.79) compared with the control group. The immunosuppressive therapy group showed significant increases in gastrointestinal, hematological, dermatological, and genitourinary side effects, as well as impaired glucose tolerance or diabetes. Hyperkalemia was more common in the control group. CONCLUSION: Immunosuppressive therapy can significantly reduce proteinuria and ESRD risk in patients with IgAN, but with a concomitant increase in adverse reactions. Therefore, care is required in the application of immunosuppressive agents in IgAN.

Expression of the intrarenal angiotensin receptor and the role of renin-angiotensin system inhibitors in IgA nephropathy.

The critical role of the intrarenal renin-angiotensin system (RAS) in the development of kidney disease has been well demonstrated in animal and cell-culture experiments, but evidence from human kidney tissues is lacking. In this study, we screened 438 patients with IgA nephropathy (IgAN) and analyzed their clinical characteristics. Renal biopsy revealed the expression of angiotensin II type 1 receptor (AT1R), angiotensin II type 2 receptor (AT2R), and MAS receptor (MASR) in the tissues of 260 patients not treated with RAS inhibitors, 32 patients treated with angiotensin-converting enzyme inhibitors (ACEIs), and 89 patients treated with angiotensin receptor blockers (ARBs). The correlations in expression among these three receptors and the results of Oxford typing were analyzed, together with the ability of ACEIs and ARBs to reduce proteinuria and the effects of ARBs on AT1R and AT2R expression. The results showed significantly higher AT1R, AT2R, and MASR expression in the M1 group (mesangial score > 0.5) than in the M0 group (mesangial score < 0.5), significantly higher AT1R expression in the S1 group (presence of segmental glomerulosclerosis) than in the S0 group (absence of segmental glomerulosclerosis); AT1R expression in the C2 group (crescent formation > 25%) was significantly higher than in the C0 (crescent formation = 0) and C1 (crescent formation < 25%) groups. Patients treated with an ARB for < 6 months had significantly lower urinary protein levels than those taking these drugs for > 6 months. These findings imply that overexpression of AT1R on the mesangial cells of IgAN patients is associated with mesangial cell proliferation, glomerular segmental sclerosis, and crescent formation. In addition, long-term administration of ARB may decrease the efficacy of these medications in terms of reducing proteinuria.

The correlation between peripheral leukocyte telomere length and indicators of cardiovascular aging.

OBJECTIVES: To investigate the relationship between telomere length in peripheral blood white cells and cardiovascular function in a healthy, aging Han Chinese population. METHODS: In 2012, peripheral blood leukocytes were obtained from 139 healthy individuals in Beijing, China, and telomere restriction fragment (TRF) length was assayed using a digoxigenin-labeled hybridization probe in Southern blot assays. Indicators of cardiovascular function were also evaluated, including electrocardiograms (ECG), (RR, P, PR, QRS, ST and T intervals); blood pressure (BP), (SBP, DBP, PP, PPI); cardiovascular ultrasound (left ventricular ejection fraction, LVEF); mitral early and late diastolic peak flow velocity (MVE and MVA); and lipid indices (TC, TG, HDL, LDL, LCI). The relationships of these cardiovascular indictors to telomere length were evaluated. RESULTS: No correlations were found between telomere length and ECG, BP or lipid indices even after adjustment for age. Correlations were found between TFR length and some cardiovascular ultrasound indictors (D, MVEA, MVEDT, MVES, MVEL, MVEI, IMT), but these were not seen after adjusting for age. CONCLUSIONS: We did not find that leukocyte TFR length was associated with cardiovascular ultrasound indictors, ECG, BP, or lipid indices in this population of healthy Han Chinese individuals. Telomere length may serve as a genetic factor in biological aging.

Effects of decline in renal function with age on the outcome of asymptomatic carotid plaque in healthy adults: a 5-year follow-up study.

BACKGROUND: It has been long suggested that abnormal clinical factors in the body, such as dyslipidemia and diabetes, can affect the presence of atherosclerosis. However, few studies on the effect of factors within the normal range, such as the loss of renal function with age, on the prevalence of atherosclerosis are few know in healthy individuals. The aim of this study was to investigate risk factors affecting the presence of asymptomatic carotid plaques in a middle-aged and elderly healthy population. METHODS: In this regard, we prospectively evaluated 245 healthy individuals (98 males and 147 females) at baseline and after 5 years. Changes in the presence of carotid plaque between 2003 and 2008 were categorized into four groups, i.e. subjects without plaque at entry (n = 165): Group 1 (without plaque on two occasions, n = 129) and Group 2 (with nascent plaque at follow-up, n = 36); subjects with plaque at entry (n = 80); Group 3 (with plaque regression at follow-up, n = 29) and Group 4 (with plaque on two occasions, n = 51). RESULTS: Univariate analysis showed that the positive rate of carotid plaques in males was higher than that in females at the baseline, and that a significantly inverse correlation existed between the prevalence rate of plaque and aging. Logistic regression analysis of cross-sectional research showed that independent risk factors for the prevalence of atherosclerosis were male gender, lower estimated glomerular filtration rate (eGFR) and higher low-density lipoprotein cholesterol (LDL-C) at the baseline, and older age and lower eGFR were involved in the presence of carotid plaques at follow-up point. However, logistic regression analysis of the longitudinal data showed that older age, decreased eGFR and increased systolic blood pressure (SBP) independently predicted the presence of carotid plaques after 5 years in subjects without plaque at entry. In addition, in subjects with plaque at entry, age, changes in eGFR and the baseline levels of serum albumin (ALB) and serum total bilirubin (BIL) dependently influenced the outcome of carotid plaque. CONCLUSION: Physiological decline of renal function, together with advancing age, was an independent risk factor which consistently affected the presence of carotid atherosclerosis in two categories of healthy individuals.

Down-regulation of S-adenosyl-L: -homocysteine hydrolase reveals a role of cytokinin in promoting transmethylation reactions.

S-adenosyl-L: -homocysteine hydrolase (SAHH) is a key enzyme for maintenance of cellular transmethylation potential. Although a cytokinin-binding activity had been hypothesized for SAHH, the relation between cytokinin and transmethylation reactions has not been elucidated. Here we show that, of the two Arabidopsis thaliana SAHH genes, AtSAHH1 has a much higher expression level than AtSAHH2. A T-DNA insertion mutant of AtSAHH1 (sahh1-1) and the RNA interference (RNAi) plants (dsAtSAHH2) accumulated a higher level of cytokinins, exhibited phenotypic changes similar to those of cytokinin-overproducers, and their global DNA methylation status was reduced. On the other hand, cytokinins positively regulate the transmethylation pathway genes, including AtSAHH1, AtADK1 (for adenosine kinase), and this regulation involves the cytokinin activity. Furthermore, expression of three cytosine DNA methyltransferase genes examined was inducible by cytokinin treatment. Unlike adenine and adenosine which are SAHH inhibitors, the adenine-type cytokinins have no effect on SAHH activity at protein level. Changing of endogenous cytokinin levels by transgene expression resulted in alterations of DNA methylation status in the sahh1-1 background, suggesting that cytokinins promote DNA methylation, at least under transmethylation stringent conditions. These data demonstrate that the phytohormone cytokinin plays a role in promoting transmethylation reactions, including DNA methylation.