bluuebunny/crossref_metadata_2025 huggingface dataset:
PS-B03-9: EPLERENONE PREVENTS CARDIAC FIBROSIS BY INHIBITING ANGIOGENESIS IN UNILATERAL URINARY OBSTRUCTION RATS
Authors: Chang Yi , Ben Ying , Li Hui , Shimosawa Tatsuo , Xu Qingyou
Published: January 2023

Objective:

Cardiovascular disease constitutes the leading cause of mortality in patients with chronic kidney disease (CKD), which is termed cardiorenal syndrome type 4 (CRS-4). The aim of our experiments was to clarify the relationship between angiogenesis and endothelial-mesenchymal transition (End-MT) and the the development of pathological cardiac remodeling and fibrosis in unilateral urinary obstruction (UUO) rats. Also, our study was to confirm eplerenone prevents cardiac fibrosis by inhibiting angiogenesis in unilateral urinary obstruction rats.

Design and method:

We used a 180-day rat model of unilateral ureteral obstruction (UUO) to replicate the CRS model. Using eplerenone, a blocker of mineralocorticoid receptor (MR), to test the effect of aldosterone in cardiac fibrosis induced by UUO. HE staining was performed to observe the pathology of myocardial tissue. The degree of myo-cardial tissue fibrosis was observed by Masson and Sirius red staining. Immunohistochemical staining was applied to detect the expression of CD34 and CD105 in myocardial tissue, and immunofluorescent staining was performed to examine the expression of CD34, COLI/COLIII and alpha-SMA. The expression of signal pathway-related protein VEGFA, VEGFR2, nuclear factor kappa-B and IL-1 beta were tested by western blot. RT-PCR was used to detect the mRNA levels of SGK-1, nuclear factor kappa-B and IL-1beta.

Results:

The results shows that the development of pathological cardiac remodeling and cardiac dysfunction in UUO rats. Moreover, there was more angiogenesis and endothelial-mesenchymal transition (End-MT) in the UUO group, and these effects were inhibited by eplerenone.

Conclusions:

The results indicated that this cardiac fibrosis was associated with angiogenesis and endothelial-mesenchymal transition (End-MT) related to aldosterone and mineralocorticoid receptor (MR) activation. Moreover, in association with the MR/IL-1beta/VEGFA signaling pathway, early treatment with the MR antagonist eplerenone in rats with UUO-induced CKD may significantly attenuate MR activation and cardiac fibrosis.
PS-B03-13: USEFULNESS OF SEROLOGIC APE1/REF-1 AS A BIOMARKER FOR VASCULAR INFLAMMATION IN APOE DEFICIENT MICE
Authors: Lee Yu Ran , Joo Hee Kyoung , Lee Eun Ok , Kim Sungmin , Jin Hao , Choi Yeon Hee , Choi Eun Ju , Jeon Byeong Hwa
Published: January 2023

Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/Ref-1) is an essential multifunctional protein involved in DNA base-excision repair and in redox regulation of several functional proteins including transcription factors. However, the role of APE1/Ref-1 in atherosclerosis is unclear. we investigated the role of APE1/Ref-1 in atherosclerotic apolipoprotein E deficient (ApoE-/-) mice fed with a Western-type diet. We found that serologic APE1/Ref-1 was strongly correlated with vascular inflammation in these mice. Neutrophil/lymphocyte ratio (NLR), endothelial cell/macrophage activation, and atherosclerotic plaque formation, reflected by atherosclerotic inflammation, were increased in the ApoE-/- mice fed with a Western-type diet. APE1/Ref-1 expression was upregulated in aortic tissues of these mice, and was co-localized with cells positive for cluster of differentiation 31 (CD31) and galectin-3, suggesting endothelial cell/macrophage expression of APE1/Ref-1. Interestingly, APE1/Ref-1 plasma levels of ApoE-/- mice fed with a Western-type diet were significantly increased compared with those of the mice fed with normal diet (15.76 ± 3.19 ng/mL vs. 3.51 ± 0.50 ng/mL, p < 0.05), and were suppressed by atorvastatin administration. Correlation analysis showed high correlation between plasma APE1/Ref-1 levels and NLR, a marker of systemic inflammation. The cut-off value for APE1/Ref-1 for predicting atherosclerotic inflammation at 4.903 ng/mL showed sensitivity of 100% and specificity of 91%. We conclude that APE1/Ref-1 expression is upregulated in aortic endothelial cells/macrophages of atherosclerotic mice, and that plasma APE1/Ref-1 levels could predict atherosclerotic inflammation.
PS-B04-3: SHORT-TERM LOW IODINE DIET EXACERBATES VASCULAR REACTIVITY WITHOUT ALTERING THYROID HORMONE PROFILES IN STROKE-PRONE SPONTANEOUSLY HYPERTENSIVE RATS
Authors: Moseki Phillip , Graham Delyth , Salt Ian , Combet Emilie
Published: January 2023

Objective:

Iodine is an essential microelement required for thyroid hormone (TH) synthesis and regulation. Recent evidence links iodine to direct cardiovascular functional changes independent of TH. We aimed to determine the short-term effect of a low iodine diet on cardiovascular parameters in young Wistar Kyoto (WKY) and stroke-prone spontaneously hypertensive (SHRSP) rats.

Design and method:

5-week-old WKY and SHRSP males and females (n = 5–7 per group) were assigned a normal (NID) or low iodine (LID) diet for 4 weeks. Iodine content was 1.2 mg/kg for NID and 0.211 mg/kg for LID. Tail cuff blood pressure (BP) and body weight were measured pre-diet and weekly. Transthoracic echocardiography, food intake, water consumption, and urine production were determined pre-diet and fortnightly. At sacrifice, thyroid tissue was weighed and snap-frozen for sodium iodide symporter (NIS) gene expression. Plasma was collected for thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), and free thyroxine (fT4) measurement. Third-order mesenteric arteries were assessed for vascular function using wire myography.

Results:

Baseline TSH, fT3, and fT4 levels were not significantly different between strains. LID did not influence food intake, body weight, thyroid weight, left ventricular (LV) mass, relative wall thickness (RWT) or BP. TSH levels, but not fT3 or fT4, significantly increased by 63.3% in SHRSP males (p = 0.0002) and 74.5% in females fed LID (p = 0.018) but not in WKY when compared to strain, sex- and age-matched rats fed NID. NIS expression significantly increased by 3.27-fold in WKY males fed LID when compared to WKY males fed NID (p = 0.03) but not in SHRSP males. A similar trend in NIS expression was observed in WKY females fed LID. Water intake/urine output ratio significantly increased by 53.62% in SHRSP females fed LID compared to SHRSP females fed NID (p = 0.04). Trends towards reduced stroke volume (SV) and cardiac output (CO) were observed in males fed LID compared to those fed NID irrespective of strain. Vascular reactivity to U46619 in third-order mesenteric resistance arteries was significantly increased by 24.9% in SHRSP males fed LID compared to SHRSP males fed NID (p = 0.03). A similar trend was evident in SHRSP females fed LID when compared to SHRSP females fed NID.

Conclusions:

Our results demonstrate that short-term LID increases vascular reactivity in SHRSP male rats and is associated with altered expression of genes that encode iodine transport proteins yet independent of thyroid hormone levels.
PS-B04-4: A NOVEL HNF4A COREPRESSOR IRF2BP2: ITS ROLE IN THE GLUCONEOGENIC GENE REGULATION VIA BIOCHEMICALLY LABILE INTERACTION
Authors: Kouketsu Takumi , Yokoyama Atsushi , Sawatsubashi Shun , Shima Hiroki , Igarashi Kazuhiko , Sugawara Akira
Published: January 2023

Hepatocyte nuclear factor 4α (HNF4α) has an essential role in controlling the expression of variety of genes involved in key metabolic pathways including gluconeogenesis in the liver. Though mechanistic and physiological significance of proliferator-activated receptor-gamma co-activator-1α (PGC-1α) for HNF4α-mediated transcriptional activation models for gluconeogenic genes is well characterized, transcriptional repression of HNF4α for those genes still remains to be examined. In this study, we applied novel proteomic techniques to evaluate the HNF4α interactome including biochemically labile binding proteins. From the experiment, we identified interferon regulatory factor 2 binding protein 2 (IRF2BP2) as a novel HNF4α corepressor, with which its interaction could not be detected by conventional immunoprecipitation. IRF2BP2 repressed transcriptional activity of HNF4α dependent on its E3 ubiquitin ligase activity. Deficiency of IRF2BP2 gene in HepG2 cells induced gluconeogenic genes comparable to the forskolin-treated wild type HepG2 cells. Together, these results suggest the role of IRF2BP2 as a novel class of nuclear receptor coregulator.
PS-B04-5: AMELIORATIVE POTENTIAL OF COMBINATION OF VITAMIN D AND SILDENAFIL AGAINST MONOCROTALINE-INDUCED PULMONARY HYPERTENSION IN RATS VIA ACTIVATING ENOS
Authors: Yadav Harlokesh Narayan , Shah Sadia
Published: January 2023

Objective:

The life expectancy in PAH is very less, and only symptomatic treatment is available. Patients with pulmonary hypertension are mostly diagnosed with co-existing vitamin D deficiency. In PAH, there is an increase in the level and expression of PDE 5 enzyme that results in increased degradation of cGMP but there is also a simultaneous decrease in the activation of cGMP due to a subsequent decrease in eNOS mediated nitric oxide synthesis. Thus, limiting the efficacy of sildenafil as monotherapy in the treatment of PAH. Furthermore, vitamin D deficiency is also associated with reduced expression of eNOS mediated NO synthesis, which further decreases cGMP synthesis thus increasing disease severity. Hence, this study was undertaken to study the combined effect of sildenafil and vitamin D therapy in monocrotaline-induced PAH in rats.

Design and method:

Rats were fed on a vitamin D deficient diet with exposure to filtered fluorescent light to induce vitamin D deficiency. PAH was induced by a single s.c. injection of MCT 50 mg/kg. Rats were divided into 6 groups: Control, MCT, MCT+Sildenafil, MCT+Vitamin D, MCT+Vitamin D+Sildenafil and MCT+L-NAME+Vitamin D+Sildenafil. Haemodynamic, echocardiographic, histopathological and biochemical parameters were analysed. The expression and level of eNOS was done using immunohistochemistry and western blot.

Results:

The effect of the vitamin D sildenafil combination group was significantly higher than the vitamin D and sildenafil treated alone groups. This protective effect of vitamin D sildenafil combination in PAH is attenuated when administered with L-NAME (20 mg/kg). Furthermore, the administration of MCT reduced the expression of eNOS, which was significantly reversed by the treatment with vitamin D sildenafil combination compared to vitamin D and sildenafil alone.

Conclusion:

The effect of vitamin D in the treatment of PAH is comparable to sildenafil alone and is further improved when given in combination with sildenafil. Moreover, if pulmonary hypertension is accompanied by vitamin D deficiency it results in increased disease severity of PAH. Thus, sildenafil when combined with vitamin D may exert a synergistic effect in amelioration of symptoms and disease severity in patients of pulmonary hypertension.
PS-B04-8: YM750, AN ACAT1 INHIBITOR, REDUCES ALDOSTERONE SECRETION BY DECREASING ADRENAL CYP11B2 EXPRESSION
Authors: Shimada Hiroki , Otsubo Yuri , Hata Shuko , Sato Ikuko , Yamazaki Yuto , Yokoyama Atsushi , Suagwara Akira , Nakamura Yasuhiro
Published: January 2023

Primary aldosteronism (PA) is a refractory hypertension that accounts for approximately 5%-10% of hypertensive patients. aldosterone-producing adenomas and idiopathic hyperaldosteronism are known causes of PA. In aldosterone-producing adenomas, depolarization due to somatic mutations of ion channels in adrenocortical cells is considered the cause of aldosterone oversecretion.

Recently, there have been reports on the expression of various cholesterol-metabolizing enzymes in aldosterone-producing adenomas, suggesting that intracellular cholesterol metabolism is very important for aldosterone secretion. We present here the possibility that an inhibitor of Acetyl-CoA acetyltransferase (ACAT1), an enzyme that converts cholesterol to cholesteryl esters, may inhibit aldosterone secretion by depolarization in adrenal cells.

Potassium chloride and YM750, an ACAT1 inhibitor, were added to human adrenocortical carcinoma, H295R cells. Then, we measured aldosterone synthase gene, CYP11B2 mRNA expression level. As a result, the expression level of CYP11B2 decreased. Both NURR1 and NGFIB mRNA expression levels also decreased. Additionally, aldosterone production was also measured and found to be significantly decreased in the YM750 added group. Next, angiotensin II was added and the inhibitory effect of YM750 was examined. The results showed that CYP11B2 expression was not decreased. This indicates that YM750 decreased the induction of CYP11B2 expression in a potassium chloride-induced stimulus-specific manner.

The experimental results suggest that YM750 specifically inhibits CYP11B2 gene expression by cell depolarization and suppresses aldosterone secretion. However, there are few reports of cholesterol metabolism affecting CYP11B2 gene expression. In this study, we found that intracellular cholesterol metabolism may affect CYP11B2 gene expression. We plan to investigate the relationship between ACAT inhibition and CYP11B2 gene expression in detail mechanisms in the future.
PS-B04-11: THE EFFECTS OF PLANT-DERIVED COMPOUNDS AND PLANT EXTRACTS ON BLOOD PRESSURE IN AN AVP INDUCED RAT MODEL OF PRE-ECLAMPSIA
Authors: Reddy Rebecca , Govender Nalini , Baijnath Sooraj , Singh Sanil , Naicker Thajasvarie
Published: January 2023

Objective:

In resource-limited settings, such as South Africa, hypertensive disorders of pregnancy such as preeclampsia (PE), is the most common direct cause of maternal deaths. Current management of PE includes the use of pharmaceutical drugs, which are frequently associated with major side-effects and not cost effective. Globally, angiotensin-converting enzyme inhibitors (ACEi) are widely used antihypertensive drugs. As a result, patients are reliant on traditional medicine obtained from medicinal plants to manage hypertension related issues. Hence, this study aimed to determine the anti-hypertensive effects of the plant derived bioactive compounds (hesperidin and nicotinamide) and medicinal plant extract (Dombeya rotundifolia ) in a Sprague Dawley rat model induced with arginine vasopressin (AVP).

Methods:

Female Sprague Dawley rats (n = 30; pregnant AVP saline (PAVPS), pregnant AVP hesperidin (PAVPH), pregnant AVP nicotinamide (PAVPN), pregnant AVP Dombeya rotundifolia (PAVPP), and positive control; pregnant AVP captopril (PAVPC) received a continuous dose of AVP (200 ng/h) via subcutaneous mini osmotic pumps for 18 days. Treatment groups were orally dosed with either 200 mg/kg/BW of the bioactive compounds; the plant extract; or 40 mg/kg/BW of captopril over a 2-week period. Blood pressure was recorded throughout gestation and fetal and placental weights were taken following sacrifice.

Results:

Treatment groups (PAVPH, PAVPN and PAVPP) significantly (p < 0.05) reduced diastolic, systolic, and mean arterial blood pressure in AVP treated rats when compared to the control group (PAVPS). Furthermore, urine output differed significantly in the AVP-treated vs the treatment groups (p < 0.05). Moreover, placental, and individual pup weight were significantly different in the PAVPS vs PS and treatment groups (p < 0.05).

Conclusion:

This study showed that Hesperidin, Nicotinamide and Dombeya rotundifolia have the potential to cause a blood pressure lowering effect. Thus, these bioactive compounds and extract may be considered as potential molecules in the development of new naturally occurring pharmaceutical products, as a means to reduce maternal and neonatal mortality and morbidity.
PS-B05-3: CARDIOVASCULAR RESPONSES EVOKED BY LOW ENERGY CONTINUOUS VERSUS INTERMITTENT STIMULATION OF THE AORTIC BARORECEPTOR AFFERENTS IN HYPERTENSION
Authors: Salman Ibrahim M , Ameer Omar Z , McMurray Sheridan , Hassan Sarah F , Sridhar Arun , Lewis Stephen J , Hsieh Yee Hsee
Published: January 2023

Objectives:

Device-based neurostimulation of the carotid baroreceptors is a novel approach to control hypertension. We have previously demonstrated the significance of aortic baroreceptor afferent nerves as a viable alternative neuromodulation target to carotid baroreceptors in lowering mean arterial pressure (MAP) in hypertension. We have also shown that appreciable reductions in MAP do not necessarily require the use of ultrahigh stimulation parameters. In this study, we aimed to investigate if energy consumption for neuromodulation of aortic baroreceptor afferents could be lowered further by using intermittent as opposed to continuous stimulation.

Design and method:

In male anesthetized spontaneously hypertensive rats (SHRs), the effects of continuous (20 sec) versus intermittent (5 sec ON/3 sec OFF and 5 sec ON/5 sec OFF for 20 sec) stimulation of the left aortic depressor nerve (ADN) on MAP, heart rate (HR), mesenteric (MVR) and femoral (FVR) vascular resistance were assessed using low (5 Hz) and high (15 Hz) frequencies delivered at 0.4 mA and 0.2 ms.

Results:

Continuous and intermittent low frequency stimulation produced similar sustained decreases in MAP, HR, MVR and FVR. Continuous high frequency stimulation produced larger reductions in MAP, HR, MVR and FVR compared with all low frequency and/or intermittent high frequency stimulations.

Conclusions:

Low charge intermittent stimulation of the aortic baroreceptor afferents maintains the required reductions in MAP levels in hypertension and intermittent delivery of the electrical stimulus can further lower energy consumption for neuromodulation. Clinically, these findings may provide useful insight for studies using baroreflex modulation in resistant hypertension and other cardiovascular diseases.
PS-B05-4: COMPARATIVE EFFECTS OF RENAL DENERVATION IN DIFFERENT STAGES OF HYPERTENSION ON CARDIAC, RENAL, AND ADIPOSE PATHOLOGY IN DAHL SALT-SENSITIVE RATS
Authors: Nagata Kohzo , Tagami Kaito , Okuzawa Toko , Hayakawa Misaki , Nomura Akane , Nishimura Tomo , Furukawa Nozomi , Sakabe Nanako , Ikeda Katsuhide , Kobuchi Shuhei , Kitada Kento , Fujisawa Yoshihide , Nishiyama Akira , Murohara Toyoaki
Published: January 2023

Objective:

Renal denervation (RDN) has emerged as a novel therapy for resistant hypertension. In Dahl salt-sensitive (DahlS) rats, RDN does not prevent the development of hypertension but attenuates the progression of hypertension. We have now investigated the comparative effects of RDN in early versus advanced stages of hypertension on cardiac, renal, and adipose tissue pathology in DahlS rats.

Design and method:

Male DahlS rats fed an 8% NaCl diet after 6 weeks of age were subjected to RDN or sham surgery at 7 (early stage) or 9 (advanced stage) weeks. In the RDN groups, all visible nerves along the vessels were cut and the vessels were painted with a solution of 10% phenol in absolute ethanol. In contrast, in the sham-operated groups, the kidneys were exposed but the vessels were not stripped or coated with phenol. At 12 weeks, left ventricular (LV), renal, and adipose tissue were excised for analysis.

Results:

Successful RDN was confirmed by determination of renal norepinephrine content in each rat subjected to RDN less than 10% of the mean values of those in the sham-operated groups. Although both stages of RDN modestly attenuated blood pressure elevation, they improved LV diastolic function and fibrosis and attenuated macrophage infiltration and expression of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α) genes in the heart, to a similar extent. In addition, both stages of RDN similarly reduced macrophage infiltration in glomeruli, the glomerulosclerosis index, the tubulointerstitial injury score as well as expression of MCP-1 and TNF-α genes in the kidney. The early stage group showed reductions in both retroperitoneal fat mass and adipocyte cross-sectional area, whereas the advanced stage group did an increase in fat mass without any change in adipocyte size.

Conclusions:

Both early and advanced stages of RDN mildly attenuated hypertension as well as ameliorated cardiac and renal injury, to a similar extent, in salt-loaded DahlS rats. The anti-hypertensive effect of RDN is thus likely attributable primarily to improved renal pathology. These results also suggest a possible crosstalk among the kidney, cardiovascular system, and adipose tissue via neural mechanisms in salt-sensitive hypertension.
PS-B05-12: ANTIHYPERTENSIVE AND CARDIO-PROTECTIVE POTENTIAL OF O. SANCTUM LEAVES EXTRACT IN L-NAME INDUCED HYPERTENSIVE RATS
Authors: Kumar Abhishek , Sharma Bechan
Published: January 2023

Objective:

There are approximately 26% of adults in the world who suffer from hypertension, which is the most common cardiovascular disease. Essential hypertension is mainly caused by endothelial dysfunction which results from nitric oxide (NO) deficiency. The present study sought to determine the impact of O. sanctum leaf extract (OS) in protecting against L-NAME induced hypertension and oxidative stress in wistar rats.

Design and method:

A non-specific nitric oxide inhibitor, L-NAME, (40 mg/kg/day), was administered to male Wistar rats to induce hypertension. CoQ10 was used as a standard anti-hypertensive compound. All of the other groups received L-NAME combined with OS extract (200 mg/kg/day) orally for three weeks. Following the treatment, hemodynamic parameters were measured using direct cannulation. The lipid profile, kidney and cardiac functions, as well as markers of oxidative stress were evaluated. The results were expressed as mean ± SD.

Results:

L-NAME was found to cause high blood pressure, NO depletion, oxidative imbalance and damage in cardiac and kidney function in animals. The Cardiac markers enzyme level were significantly increased in L-NAME only group whereas, the CO-treatment group had lower lower of Cardiac markers as compared to control as well as L-NAME group. In hypertensive rats, OS treatment significantly lowers the expression of angiotensin converting enzyme (ACE) and mineralocorticoid receptor expression in hypertensive rats. Concurrent treatment with L-NAME and OS extract prevented the all injuries without affecting the heart rate or raising blood pressure.

Conclusions:

The results confirm O. Sanctum leaves extract antihypertensive action and indicate its protective properties in the L-NAME induced hypertension model of rats, likely due to the presence of rich antioxidant potential and by inhibiting the inflammation.
PS-B07-4: ADMINISTRATION OF AMINO ACIDS PROVOKES EXPRESSION OF PRO-FIBROTIC GENES IN MURINE CULTURED FIBROBLAST CELLS
Authors: Oshida Takuma , Miyashita Kazutoshi , Kubo Akiko , Sato Masaaki , Fujii Kentaro , Ryuzaki Masaki , Uto Asuka , Nakamura Toshifumi , Kinouchi Kenichiro , Kobayashi Sakiko , Ito Hiroshi
Published: January 2023

Objective:

Diabetic kidney disease (DKD) has been the most common cause of end-stage renal disease (ESRD) which leads to hemodialysis for more than 20 years in Japan. Various reports have been published on the mechanisms underlying the progression of DKD, however, many details remain unclear. We investigated the mechanisms underlying the progression of renal fibrosis and kidney injury in hyperglycemia from the viewpoint of metabolic alteration in the kidney by using streptozotocin-treated mice (STZ mice).

Design/Methods:

8 weeks old ICR mice were treated with streptozotocin (200 mg/kg intra-peritoneally), to produce type 1 diabetes mellitus model mice. The kidneys of those mice were collected 4 weeks after STZ treatment and examined for metabolites that were altered in the kidneys of STZ mice by metabolome analysis. Amino acids that were increasing in the kidneys of STZ mice were administered to L929 murine fibroblast cells, and expression of pro-fibrotic genes were examined.

Results:

STZ-treatment caused progression of renal fibrosis in mice under both low- and high-protein diets. Metabolome analysis of the kidneys in STZ mice showed marked alterations of amino acids in the kidneys. Increased levels of branched chain amino acids (BCAAs) such as valine and leucine were observed. Among these amino acids, leucine administration to L929 cells resulted in increased expression of genes promoting renal fibrosis.

Conclusions:

Alterations of BCAAs in the kidneys due to hyperglycemia in STZ mice may affect progression of renal fibrosis and kidney injury. We are now investigating the mechanism by which BCAAs contribute to renal fibrosis.
PS-B07-6: L-ARGININE SUPPLEMENTATION SUBSTANTIALLY ATTENUATES HYPERTENSION BUT NOT CARDIAC INJURY IN RATS WITH METABOLIC SYNDROME
Authors: Tagami Kaito , Okuzawa Touko , Hayakawa Misaki , Cui Xixi , Obara Natsuki , Kunimatsu Asuko , Koide Mayako , Teranishi Tamami , Furukawa Nozomi , Sakabe Nanako , Ikeda Katsuhide , Murohara Toyoaki , Nagata Kohzo
Published: January 2023

Objective:

L-arginine is not only a building block for protein but also a physiological substrate for the synthesis of nitric oxide (NO) and plays a regulatory role in signal transduction pathways in cells. Dietary L-arginine supplementation reduced fat mass both in Zucker diabetic fatty rats and in diet-induced obese rats. However, little is known about the effects of L-arginine on cardiac morphology and function in metabolic disorders. We have now examined the effects of L-arginine on cardiac pathology in DahlS.Z-Leprfa/Leprfa (DS/obese) rats, an animal model of metabolic syndrome (MetS).

Design and method:

DS/obese rats and their homozygous lean (DahlS.Z-Lepr+/Lepr+, or DS/lean) littermate controls were fed a purified control diet and were supplemented with 0.50% L-arginine-HCl or 0.85% L-alanine (isonitrogenous control) in drinking water from 13 to 17 weeks of age.

Results:

L-arginine supplementation did not affect body weight, visceral and subcutaneous fat mass, insulin resistance, or food and water intake in DS/obese rats, but substantially alleviated hypertension. However, left ventricular (LV) and cardiomyocyte hypertrophy and the upregulation of myocardial fetal-type gene expression, macrophage infiltration in the heart, and increased perivascular and interstitial fibrosis of the LV myocardium and the upregulation of fibrosis-related gene expression were not improved by such intervention. Additionally, L-arginine did not ameliorate impairments of Doppler- or micromanometer-derived indices of LV diastolic function. None of these parameters were influenced by L-arginine supplementation in DS/lean rats.

Conclusions:

L-arginine supplementation substantially ameliorated hypertension but did not attenuate LV remodeling or diastolic dysfunction in this model of MetS. These data suggest that in addition to its role as a precursor of NO, L-arginine may play a role as a functional amino acid that modulates growth and inflammation.
PS-B08-7: L-CARNITINE AMELIORATES DIABETIC KIDNEY DISEASE BY ALLEVIATING MITOCHONDRIAL ABNORMALITY IN SDT-FATTY RATS
Authors: Ito Sakuya , Taguchi Kensei , Kaida Yusuke , Kodama Goh , Moriyama Tomofumi , Yokota Yunosuke , Shinohara Masami , Tashiro Kyoko , Fukami Kei
Published: January 2023

Background and Aims:

Abnormal fatty acid metabolism is associated with the progression of diabetic kidney disease (DKD). Carnitine plays a central role in β;-oxidation and energy production by transporting long-chain fatty acids from the cytoplasm to the mitochondria. Recently, we found that significant ectopic fat was accumulated in the kidney tissue in DKD patients compared with those in minimal change kidney disease patients. Juvenile visceral steatosis (jvs) mice, described as an animal model for systemic carnitine deficiency, introduce a marked ectopic fat accumulation in the kidney. These findings suggest that abnormal carnitine dynamics in DKD cause ectopic fat accumulation due to abnormality of the fatty acid metabolism. However, the association between abnormalities of carnitine metabolism and the progression of DKD is unknown.

Method:

Spontaneously Diabetic Torii (SDT) fatty rat, an obese type 2 diabetic model was used. Unilateral nephrectomy was performed and 0.3% salt water was administered at 6 weeks of age, and created a renal dysfunction model in SDT fatty rat (DKD model). Age-matched male Sprague-Dawley (SD) rat was used as a control. Experiment 1: We compared 3 groups; SD rats (n = 8), SDT fatty rats (n = 8), DKD rats (n = 8). Experiment 2: We compared 3 groups; SD rats with sham operation (n = 8), DKD rats (n = 7), DKD rats treated with L-carnitine administration (0.75% L-carnitine diet) for 10 weeks (n = 6). All rats were sacrificed at 17 weeks old. Carnitine was measured by the enzyme cycling method. Acylcarnitine was analyzed by the tandem-mass spectrometry.

Results:

Plasma and renal free carnitine levels and short/middle-long chain acylcarnitine ratio were significantly decreased in DKD rats compared with those in SD and SDT fatty rats. The renal expression levels of organic cation / carnitine transporter 2 (OCTN2), carnitine palmitoyl transferase 1a (CPT1a), CPT2 and carnitine acetyltransferase (CrAT) were significantly decreased in DKD rats compared with those in SD and SDT fatty rats. Similarly, peroxisome proliferator-activated receptor γ co-activator 1α (PGC1α) activity was decreased in DKD rats. L-carnitine administration significantly improved renal function, urinary albumin excretion, interstitial fibrosis and renal ectopic fat accumulation in DKD model rats. L-carnitine administration ameliorated the decrease of renal OCTN2, CPT1a, CPT2 and CrAT protein expression, and significantly improved PGC1α activity in DKD model rats. Furthermore, L-carnitine administration mitigated lipid peroxidation and mitochondrial dysfunction in DKD rats.

Conclusion:

L-carnitine administration might be a promising therapeutic strategy for improving renal function by alleviating mitochondrial dysfunction in DKD rat model.
PS-B08-9: INHIBITION OF PERIOSTIN PROTECTED FROM EXACERBATION OF INFLAMMATION IN RHABDOMYOLYSIS-INDUCED ACUTE KIDNEY INJURY
Authors: Muratsu Jun , Taniyama Yoshiaki , Sanada Fumihiro , Shibata Kana , Koibuchi Nobutaka , Rakugi Hiromi , Morishita Ryuichi
Published: January 2023

Objective:

Rhabdomyolysis is the breakdown of damaged skeletal muscle and the leakage of muscle-cell contents, including myoglobin, and other sarcoplasmic proteins into the circulation. These products may be filtered through the glomeruli, leading to acute kidney injury (AKI) via several mechanisms, such as inflammation and intratubular obstruction secondary to protein precipitation. New therapeutic strategy to lessen AKI are urgently needed. Thus far, several cellular pathways, nuclear factor kappa beta (NF-KB) as well as including pro-inflammatory effects on epithelial and tubular epithelial cells, have been identified as the major avenues for the initiation of the matrix-producing cells in AKI. Recently, it is suggested that periostin, extracellular matrix, is involved in the development of inflammation through the modulation of NF-KB pathway. However, periostin on the progression of the inflammation protection in AKI due to rhabdomyolysis is unclear. This study aimed to investigate the role of periostin in a rhabdomyolysis mice model of AKI.

Design and method:

In vivo, rhabdomyolysis-induced AKI was created by an intramuscular injection of 50% glycerol (5 mg/kg body weight). The expression level of periostin during the progression of acute renal failure after glycerol intramuscular injection for C57BL/6J wild type (WT) mice model was investigated. The mice were sacrificed at 72 hours after glycerol injection. We have developed periostin null mice to examine the role of periostin on acute renal failure. The role of periostin were further investigated through in vitro methods. In vitro, the development of renal inflammation is associated with NF-KB pathway. To investigate the function of periostin, we administrated Hemin(100uM) on NIH-3T3 fibroblast cells and the subsequent signaling pathways was examined.

Results:

The expression of periostin was highly increased, peaking at approximately 72 hours after gycerol injection. Inflammation-associated mRNA such as Monocyte Chemotactic Protein-1, tumor necrosis factor-alpha and IL6 expression and tubular injury score in H-E staining was more reduced in periostin null mice than WT mice at 72 hours after gycerol injection. Finally, an intraperitoneal injection of periostin antibody suppressed the mortality. These findings suggest a causal link between periostin and inflammation in AKI induced by rhabdomyolysis. In addition, an intraperitoneal injection of antibody for periostin antibody might be a new therapeutic strategy against the development of AKI induced by rhabdomyolysis.

Conclusions:

Periostin were highly expressed in kidney via rhabdomyolysis, and were a positive regulator of AKI. Targeting periostin might offer a new therapeutic strategy against the development of renal failure.
PS-B08-10: COMBINATION OF SYSTEMIC ATRAP DEFICIENCY WITH ANGIOTENSIN II STIMULATION ACCELERATES THE DEVELOPMENT OF DIABETIC NEPHROPATHY IN STREPTOZOTOCIN TREATED MICE
Authors: Taguchi Shinya , Azushima Kengo , Wakui Hiromichi , Suzuki Toru , Urate Shingo , Abe Eriko , Tanaka Shohei , Tsukamoto Shunichiro , Tamura Kouichi
Published: January 2023

Objective:

One of the obstacles toward understanding the pathophysiology of diabetic nephropathy (DN) has been the lack of reliable animal models that faithfully replicate features of human DN. Angiotensin II (Ang II) type 1 receptor (AT1R)-associated protein (ATRAP) promotes internalization of AT1R from the cell surface into the cytoplasm, resulting in the suppression of AT1R signaling pathway. We have recently reported that systemic ATRAP deficiency exaggerates streptozotocin (STZ)-induced DN via an activation of renal renin-angiotensin system (RAS) (Haruhara K, et al. Kidney Int 2022). However, STZ-induced diabetic ATRAP knockout mice still exhibited a modest increase in albuminuria with limited pathological changes just in glomerulus. To establish more robust DN models, we examined the effect of Ang II stimulation on the development of DN in STZ-treated ATRAP knockout mice.

Design and method:

Male eight weeks old C57BL/6 mice (Ctrl) and systemic ATRAP-knockout mice (KO) were divided into three groups: 1) Ctrl-STZ, 2) Ctrl-STZ-Ang II, and 3) KO-STZ-Ang II. Hyperglycemia was induced by intraperitoneal injection of 55 mg/kg STZ for consecutive 5 days. From 4 weeks after STZ administration, Ang II (1000 ng/kg/min) was continuously administered by osmotic mini-pumps for 6 weeks. During the experimental period, body weights and levels of blood glucose were measured every 2 weeks. At 6 and 10 weeks after STZ administration, 24-hour urine samples were collected in metabolic cages, and urinary albumin excretion (UAE) was evaluated by ELISA. At the end of experimental period, mice were euthanized to evaluate renal pathological changes.

Results:

During the experimental period, body weight gain and levels of blood glucose were not significantly different between the three groups. Nonetheless, although levels of UAE at 6 weeks after STZ administration were still modest and comparable between the three groups, levels of UAE only in the KO-STZ-Ang II group were remarkably increased compared to those in the Ctrl-STZ and Ctrl-STZ-Ang II groups at 10 weeks after STZ administration (679.1 ± 583.7 vs 69.9 ± 10.0 vs 61.3 ± 8.2 μg/day, respectively). Furthermore, in the KO-STZ-Ang II group, exacerbation of mesangial expansion and interstitial fibrosis was observed.

Conclusions:

In STZ-induced diabetic mice, combination of systemic ATRAP deficiency with Ang II stimulation accelerated the development of DN, suggesting a potential to become a promising mouse model replicating key features of human DN.
PS-B08-12: THE REGULATORY EFFECTS OF HYPERTENSION-RELATED CIRCULAR RNA GRB10 IN THE KIDNEY
Authors: Maier Michelle Carla , Woods Bradley , Prestes Priscilla , Byars Sean , Eales James , Tomaszewski Maciej , Charchar Fadi
Published: January 2023

Objective:

To examine the effects of experimental reduction in the expression of circGRB10 in human kidney cells and identify its potential regulatory targets in human kidney cells.

Design and method:

Through use of small interfering RNA (siRNA), we knocked-down circGRB10 in human kidney cells (HEK293) and investigated potential downstream targets using RNA sequencing. Small RNA sequencing and total RNA sequencing were performed to investigate differentially expressed microRNAs (miRNAs) and mRNAs, respectively. Statistical significance was set as FDR < 0.01. Pathway analysis was performed using Kyoto Encyclopedia for Genes and Genomes (KEGG) on the Database Annotation Visualization Integrated Discovery (DAVID). Finally, we investigated enriched gene ontology terms.

Results:

We identified 1,483 genes showing differential expression between cells where circGRB10 was knocked down and the control cells. No miRNAs were differentially expressed between circGRB10 cells and the control. The differentially expressed genes mapped onto 66 KEGG pathways including those of relevance to protein and RNA binding.

Conclusion:

These results indicate that circGRB10 most likely operates as a direct regulator of mRNA expression in the kidney rather than through modulation of microRNAs.
PS-B09-4: SHORTER LEUKOCYTE TELOMERE LENGTH AS AN EARLY INDICATOR FOR CHRONIC KIDNEY DISEASE IN HYPERTENSIVE PATIENTS
Authors: Akinnibosun Olutope Arinola , Eales James , Nguyen Huy , Bogdanski Pawel , Szczechowska Ewa Zukowska , Denniff Matthew , Tomaszewski Maciej , Charchar Fadi
Published: January 2023

Objective:

Essential hypertension is a major risk factor for incident chronic kidney disease (CKD). This is a main reason for preference of antihypertensive medications that provide some protection against hypertension induced renal damage. Furthermore, there is abundant evidence that hypertension and CKD comorbidity worsens cardiovascular disease prognosis with increased morbidity and mortality. Onset of CKD may not be noticeable until there is evident progressive decline in the estimated glomerular filtration rate (eGFR). For this, telomere attrition may provide some early indication. Telomeres are markers of biological aging, and telomere attrition is associated with oxidative stress and inflammation. Kidney interstitial inflammation is known to play a central role in loss of renal function progressing into CKD. This study investigated the association between telomere length and renal interstitial inflammation in hypertensive patients.

Design and Methods:

Our study group consisted of 200 participants from the TRANScriptome of renaL humAn TissuE (TRANSLATE) study. Interstitial inflammation in human kidney tissue samples was assessed by histology. eGFR was calculated from serum creatinine using Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) FORMULA. Leukocyte telomere length (LTL) was quantified using quantitative polymerase chain reaction.

Results:

Mean LTL was significantly shorter in hypertensive participants (2.776 ± 0.063) compared with non-hypertensive participants (3.007 ± 0.092; P = 0.041). In hypertensive participants without CKD, renal interstitial inflammation negatively associates with leukocyte telomere length (LTL) (r = -0.483, P = 0.048), and the association remained significant after adjustment for age (r = -0.479, P = 0.041). Similar results were observed after exclusion of patients with eGFR > = 60 ml/min/1.73m2. In patients with eGFR < 60 ml/min/1.73m2, the association remained significant after adjusting for age, sex, BMI, diabetes mellitus and smoking status (r = -1.429, P = 0.011). These results show that telomere length associates with interstitial inflammation in hypertensive patients with no apparent decrease in eGFR.

Conclusions:

Hypertensive participants have shorter LTL than non-hypertensive participants, and within the hypertensive group, participants with shorter telomeres are more likely to have CKD. Telomere length may provide suitable indication to help target hypertensive patients at increased risk of developing CKD.
PS-B09-6: BIGLYCAN, A NEWLY IDENTIFIED MEDIATOR OF MINERALOCORTICOID RECEPTOR ACTIVATION-INDUCED NEPHROPATHY
Authors: Nakamura Toshifumi , Bonnard Benjamin , Ramirez Roberto Palacios , Celis Amaya Fernandez , Jaisser Frederic , Andres Natalia Lopez
Published: January 2023

Background:

The activation of mineralocorticoid receptor (MR) is known to be involved in kidney disease progression. MR antagonists (MRAs) have been reported to have beneficial effects on various kidney diseases. However, it is still unclear which mechanism underlies kidney and glomeruli injury related to MR activation. Recently, we demonstrated that aldosterone promotes proteoglycan synthesis in mitral valve interstitial cells and its association with the development of cardiac valvular disorder. Proteoglycans are glycosylated molecules sequestered in the extracellular matrix (ECM), interacting with other components of ECM. In addition, some proteoglycans are known to interact with several bioactive partners to activate cell signaling. Since increased expression of certain proteoglycans has been reported in several kidney diseases, we investigated the association between the proteoglycans expression and kidney injury upon aldosterone/MR pathway activation.

Methods:

We analyzed the alteration and localization of proteoglycan expression in the kidney of uninephrectomy/aldosterone/salt (NAS)-treated mice. The MRA eplerenone was administered to these mice to evaluate the contribution of the MR pathway in NAS-induced kidney injury. Glomeruli samples were isolated from the kidneys to assess the localized expression of proteoglycans and the glomerular injury. Additionally, we performed cellular experiments using isolated peritoneal macrophages to assess the direct effect of a proteoglycan biglycan on macrophages.

Results:

NAS treatment enhanced renal fibrosis and urinary albumin levels. Renal expression of proteoglycans was increased. Among various proteoglycans, biglycan showed increased expression, especially in the glomeruli. Isolated glomeruli samples revealed glomerular macrophage infiltration, accompanying enhanced expression of TNF-α (tumor necrosis factor-alpha), iNOS (inducible nitric oxide synthase), Nox2 (NADPH oxidase 2), CCL3 (C-C motif chemokine ligand 3), and phosphorylated NF-κB (nuclear factor-kappa B). The expression of CD86, a surface marker for M1 macrophage, also increased by 11.5-fold in the glomeruli of NAS-treated mice. These changes were blunted by eplerenone. Treatment with purified biglycan induced expression of TNF-α, iNOS, Nox2, and CCL3 in the isolated macrophages. An inhibitor of toll-like receptor 4 (TLR4) or NF-κB prevented this increase, indicating that the effect of biglycan stimulation is dependent on the TLR4/NF-κB pathway.

Conclusion:

This study identified the proteoglycan biglycan and its downstream TLR4/NF-κB/CCL3 cascade as a novel mediator of MR activation-induced glomerular injury.
PS-C17-3: ONE-YEAR TIME-SERIES OBSERVATIONS OF VARIABLE COMPONENTS OF URINE PROTEIN AND EGFR PREDICT WORSENING RENAL FUNCTION IN TYPE 2 DIABETES
Authors: Watanabe Mari , Meguro Shu , Kimura Kaiken , Furukoshi Michiaki , Masuda Tsuyoshi , Enomoto Makoto , Itoh Hiroshi
Published: January 2023

Objective:

Type 2 diabetes, along with hypertension, is a major cause of worsening renal function. It would be very meaningful if we could detect future deterioration of renal function.

Design and method:

Predictive models were created using machine learning techniques. We used the medical information database of 2533 patients who attended the outpatient clinic of our hospital between January 2003 and March 2015. The point at which the estimated glomerular filtration rate(eGFR) first falls below 60 mL/min/1.73 m2 is used as the reference point. The input period was defined as the period from the reference point to one year before the reference point. Time series during the input period for eGFR, hematocrit, and urinary protein were extracted from blood and urine tests as features for predicting worsening renal function. The primary endpoint was a 50% reduction in eGFR during the evaluation period of three years since reference point from the mean value during the input period. The optimal combination was selected to maximize prediction performance using up to 4 features considering the number of endpoints reached. The prediction results were evaluated on AUC with 10 repeated 2-fold cross validation.

Results:

Among 2533 patients, 1409 patients had the reference point. Of those, 377 patients for whom a record existed for the input and evaluation periods but did not reach the primary endpoint, and 36 patients reached the primary endpoint. The mean eGFR during the input period was 67.9 ± 8.8 mL/min/1.73 m2, the mean age was 64.9 ± 10.2, 41.6% was women. The mean AUC was 0.82 ± 0.033 when the maximum and minimum values of urinary protein, minimum of eGFR and the difference between maximum and minimum values of eGFR during the input period were used as features.

Conclusions:

In this study, we developed a prediction model for worsening renal function using time series measurements in patients with relatively preserved renal function(eGFR> 60 mL/min/1.73 m2), and the results showed that it is very important to consider the variable components of urine protein and eGFR, which are laboratory values reflecting renal impairment. Recently, SGLT2 inhibitors have been used to treat kidney disease, but this study analyzed data before the release of SGLT2 inhibitors. We would like to examine whether our model can be applied to patients taking SGLT2 inhibitors.
PS-C17-5: HYPOBILIRUBINEMIA AND HYPERTENSION AS RISK FACTORS FOR DIABETIC RETINOPATHY OF TYPE 1 AND TYPE 2 DIABETES MELLITUS
Authors: Tanaka Masami , Nishimura Takeshi , Itoh Hiroshi
Published: January 2023

Objective:

Previously, we reported that hypobilirubinemia is an important risk factor for diabetic retinopathy. On the other hand, high systolic blood pressure (SBP) is reported to be a risk factor for this condition. Therefore, we conducted this retrospective study to evaluate a significance of hypobilirubinemia and hypertension as risk factors for diabetic retinopathy of type 1 and type 2 diabetes mellitus (DM).

Design and Methods:

One hundred and thirty-one patients (59 men) with type 1 and 293 patients (159 men) with type 2 DM were included in this cross-sectional study. We compared serum total bilirubin concentration (TBC) between the patients with and without diabetic retinopathy, and compared it according to the severity of retinopathy. Logistic regression analysis was used to examine the effects of various factors on retinopathy, and the following factors were considered as independent variables: SBP, TBC, gender, age, diabetes duration, HbA1c, eGFR, and BMI.

Results:

The age, diabetes duration, BMI, HbA1c and TBC of the subjects with type 1 and type 2 DM were 54.9 + 15.0 years, 17.4 + 12.2 years, 21.9 + 3.6 kg/m2, 7.9 + 1.5%, 0.70 + 0.24 mg/dL and 64.1 + 12.8 years, 14.4 + 9.5 years, 25.4 + 5.4 kg/m2, 9.2 + 1.8%, 0.75 + 0.29 mg/dL, respectively. Forty-three (33%) patients with type 1 and 124 (42%) patients with type 2 DM patients were complicated by diabetic retinopathy, respectively. Sixty (46%) patients with type 1 and 211 (72%) patients with type 2 DM were complicate by hypertension. Among type 1 and type 2 DM patients, SBP was higher and TBC was lower significantly in patients with retinopathy than in those without retinopathy. It was shown that serum TBC was negatively associated with increasing severity of retinopathy in patients with both type 1 and type 2 DM. The results of logistic regression analysis showed that TBC was an independent explanatory factor for retinopathy of both type 1 (p = 0.001) and type 2 (p < 0.001) DM. Among type 1 diabetics, systolic blood pressure was an independent risk factor (p = 0.001), but SBP was not (p = 0.067).

Conclusions:

Low TBC might have pathophysiological significance in the onset of retinopathy for both type 1 and type 2 DM patients. On the other hand, the significance of hypertension might be higher for type 2 than type 1 DM.