Intravenous alimentation of rats in renal failure

Experiments on nephrectomized rats were made to compare the effect of oral and intravenous feeding on the degree of uremia and general status of the body. Intravenous feeding which included only essential amino acids as nitrogenous component or an insufficiently balanced mixture of essential amino acids and several replaceable amino acids (9.5% of energy value) did not produce any correcting action on the uremic status. Oral feeding with the diet containing casein (9.5% of energy value) was more effective as regards the reduction of uremia and maintenance of the general status of the body.     

D-allose protects against endotoxemic acute renal injury

D-allose is a monosaccharide. We previously reported that D-allose attenuated renal injury by inhibiting the activation of neutrophils after renal ischemia/reperfusion. Lipopolysaccharide (LPS) triggers sepsis syndrome by activating monocytes to produce proinflammatory cytokines, including tumor necrosis factor (TNF)-alpha, which potently stimulates the activation of neutrophils. This study was undertaken to examine the effects of D-allose on renal injury in the systemic inflammatory response induced by LPS administration, with emphasis on systemic TNF-alpha and the activation of neutrophils in the rat kidney. Serum and renal TNF-alpha, renal cytokine-induced neutrophil chemoattractant (CINC)-1, and myeloperoxidase (MPO) concentrations, and renal function after LPS administration were evaluated. D-allose (400 mg/kg body weight) inhibited LPS-induced increases in serum and renal TNF-alpha concentrations and renal CINC-1 and MPO concentrations after LPS administration, as well as the subsequent neutrophil-mediated renal injury. These findings may have important implications in understanding the biologic functions of D-allose. D-allose may prove useful in protecting against acute renal injury in systemic inflammatory responses to LPS.     

Milk-alkali syndrome complicated by acute renal insufficiency]

A case of the "Burnett" syndrome complicated by acute renal insufficiency is reported. Hemodialysis and normalization of the diet helped in the end to eliminate both the milk-alkali syndrome and renal insufficiency.     

Various indicators of renal function in experimental malnutrition

Study of renal function in rats during long-term choline-protein deficiency has demonstrated the development of renal failure in the late stages of experiments. After the period of recovery all the parameters under study returned to normal, with the exception of blood serum concentration of endogenous creatinine, which in experimental group animals was lower (p less than 0.025) as compared with this indicator in the control.     

Reconstruction of renal glomerular tissue using collagen vitrigel scaffold

The construction of renal glomerular tissue has provided an important tool not only for the understanding of renal physiology and pathology in blood ultrafiltration and cell dysfunction, but also in the application of tissue engineering to glomeruli regeneration and nephritic therapy. In this study, a novel method to reconstruct glomerular tissue combining cultured cells on a collagen vitrigel scaffold is described. The method consists of two newly developed techniques, one to isolate glomerular epithelial and mesangial cells rapidly from kidney, which facilitates the prolongation of cell population doublings and allows a long-term cell culture without losing cellular features, and another to prepare a stable and thin transparent collagen gel membrane termed collagen vitrigel that can facilitate three-dimensional cultures for reconstructing an epithelial-mesenchymal model. By combining the two methods, we cocultured glomerular epithelial and mesangial cells on both surfaces of the collagen vitrigel by the manipulation of two-dimensional cultures, resulting in the successful reconstruction of a three-dimensional glomerular organoid. The coculture results showed that the collagen vitrigel maintains cell growth and cell viability for more than 1 month, and surprisingly, the epithelial layer demonstrated polarity formation, which usually appears in in vivo normal epithelial cells existing at the glomerular basement membrane, but seldom appears in epithelial cells cultured in vitro. Moreover, the coculture results showed that fibronectin, an extracellular matrix component, and integrin beta1, a receptor of fibronectin, were detected in high amounts on both cells, suggesting our collagen vitrigel can provide a suitable environment for cell-cell interactions that stabilize the cell structure and may contribute to the polarity formation of epithelial cells.     

Extract of Aster glehni ameliorates potassium oxonate-induced hyperuricemia by modulating renal urate transporters and renal inflammation by suppressing TLR4/MyD88 signaling

Food Science and Biotechnology - Recent studies suggest that Aster glehni extract (AGE) reduces hyperuricemia by preventing xanthine oxidase activity. However, its effect on renal urate...     

山柰酚保护阿霉素诱导的肾损伤大鼠肾组织机制探究

目的 探究山柰酚对阿霉素诱导的肾损伤大鼠的保护作用，并初步探究其可能的作用机制。方法 采用阿霉素注射法建立肾损伤模型大鼠，分为模型组、山柰酚低、中、高剂量组、山柰酚高剂量+EX527（SIRT1特异性抑制剂）组，另设置空白对照组（n=10）；对造模当天、1周、2周、4周24 h尿液尿蛋白量进行检测；全自动生化分析仪检测血肌酐（Scr）、血尿素氮（BUN）水平；ELISA法检测肿瘤坏死因子α（TNF-α）、白介素1β（IL-1β）水平；HE染色检测肾组织病理形态学变化情况；透射电镜观察肾组织超微结构；流式细胞术检测肾组织细胞的凋亡情况；Western blot法检测肾组织中沉默信息调节因子1（SIRT1）、p38丝裂原活化蛋白激酶（p38MAPK）、p-p38MAPK、核因子κB p65（NF-κB p65）、p-NF-κB p65、B淋巴细胞瘤-2蛋白（Bcl-2）、Bcl-2相关X蛋白（Bax）、半胱氨酸蛋白酶3（Caspase-3）的蛋白水平。结果 与空白对照组相比，造模后1周、2周、4周模型组24 h尿液尿蛋白量升高，Scr、BUN、TNF-α、IL-1β水平均升高，肾组织损伤评分、组织细胞凋亡率升高，p-p38MAPK/p38MAPK、p-NF-κB p65/NF-κB p65、Bax、Caspase-3的蛋白水平升高，SIRT1、Bcl-2蛋白表达显著降低（P<0.05）；给予模型大鼠低、中、高剂量山柰酚干预后，上述指标均得到显著逆转（P<0.05），而SIRT1特异性抑制剂EX527能显著下调SIRT1的表达（P<0.05），减弱高剂量山柰酚对肾损伤的保护作用。结论 山柰酚对阿霉素诱导的肾损伤大鼠的肾组织具有保护作用，其机制可能与上调SIRT1表达，抑制p38MAPK信号通路活化，减少肾组织细胞凋亡有关。     

磷脂对肥胖诱导肾损伤保护作用的研究进展

近几年来, 中国人群尤其是儿童肥胖的发生率明显上升, 随之肥胖导致的肾病引起越来越多关注, 也对其发病机制、病理特点、防治等进行了较深入的研究。除了药物疗法及形成健康的生活方式, 功能食品营养因子在缓解或防治慢性肾脏病方面也有一定应用, 尤其功能性油脂磷脂, 其具有特殊的生理功能, 作为构成所有细胞膜的基本成分, 与肾脏病相关病理活动有一定联系。本文对肥胖性肾损伤的发病机制及磷脂结构功能进行概述, 综述了磷脂对肥胖导致肾损伤的保护作用的研究, 为开发针对肥胖引起的肾功能损伤的膳食补充剂或功能性食品提供了理论基础。     

Regulation of calf renal 25-hydroxyvitamin D-hydroxylase activities by calcium-regulating hormones

Parathyroid hormone and 1,25-dihydroxyvitamin D3 had opposite effects on calf renal 25-hydroxyvitamin D3 24-, 23-, and 1 alpha-hydroxylase activities. Parathyroid hormone administration increased renal 25-hydroxyvitamin D3-1 alpha-hydroxylase activity 7-fold while 25-hydroxyvitamin D3-23- and 24-hydroxylase activities were essentially the same as controls. Administration of 1,25-dihydroxyvitamin D3 increased 25-hydroxyvitamin D3-23-hydroxylase and 24-hydroxylase activities 4-fold and decreased 25-hydroxyvitamin D3-1 alpha-hydroxylase activity to undetectable concentrations. Vitamin D deficiency increased 25-hydroxyvitamin D3-1 alpha -hydroxylase activity 13-fold, and 25-hydroxyvitamin D3-23-hydroxylase and 24-hydroxylase activities were undetectable. These results confirm previous reports with regard to control of renal 25-hydroxyvitamin D3-24-hydroxylase and 1 alpha -hydroxylase in other species and represent new findings relative to the control of 25-hydroxyvitamin D3-23-hydroxylase. Plasma P was lower and 1,25-dihydroxyvitamin D3 higher in calves treated with parathyroid hormone, and Ca and 1,25-dihydroxyvitamin D3 were lower in the vitamin D-deficient calves. 1,25-Dihydroxyvitamin D3-treated calves had higher plasma P and lower Mg than controls. Further studies using this calf model should lead to better understanding of Ca-regulating hormones control of vitamin D metabolism.     

Effect of dietary CLA supplementation on renal inflammation in diabetic mice

Dietary conjugated linoleic acid (CLA) supplementation was studied for diabetic renal inflammation improvement through modulation of inflammatory responses and oxidative stress. ICR mice were administrated alloxan (180 mg/kg, i.p.) once and fed an AIN-93G diet, or diets containing 0.5 or 1% CLA for 8 weeks. Dietary CLA supplementation did not change body weights or ameliorate fasting blood glucose, blood urea nitrogen, and kidney MDA levels. However, dietary CLA supplementation improved plasma creatinine levels and overall inflammatory response in diabetic nephropathy by modulation of phosphorylated inhibitory kappa B and the protein levels of interleukine-1β, inducible nitric oxide synthetase, and the c-reactive protein without regulation of blood glucose levels. CLA supplementation in diabetic mice did not restore the manganese superoxide dismutase antioxidant defense system. CLA supplementation was beneficial in diabetic nephropathy through regulation of inflammatory response and has potential as an antiinflammatory terapeutic in patients with mild diabetes and diabetic complications.     

Green tea: A promising anticancer agent for renal cell carcinoma

Renal cell carcinoma (RCC) is one of the most lethal amongst the urologic malignancies, comprising three percent of all human neoplasms, and its incidence appears to be rising. RCC is refractory to both chemotherapy and radiotherapy. Therefore, the discovery of new strategies for therapeutic intervention remains a priority. Green tea (Camellia sinensis) and tea polyphenols have been proposed to exert protective effects against several types of cancer, based on preclinical and clinical trial data; however, the anticarcinogenic activity of green tea towards RCC is unknown. In this study, a targeted metabolite analysis on a green tea leaves methanolic extract was performed by HPLC/DAD and the antiproliferative activity of the extract was assayed using human renal cancer cell lines A-498 and 769-P. The total phenolic content was very high (31.8% of methanolic extract), and the main compounds were flavan-3-ols (94.3% of the total phenolic content), and especially (−)-epigallocatechin-3-gallate (35.9% of the total phenolic content). In addition, two methylxanthines – theophylline and caffeine – were also present in the extract, caffeine being the most abundant. Green tea extract strongly inhibited the growth of both RCC cell lines in a concentration-dependent manner, with IC₅₀ values of 54 ± 10 and 129 ± 28 μg/ml for A-498 and 769-P cells, respectively. This is the first report showing that green tea is likely to be an effective anticancer agent for renal cell carcinoma.     

Mediterranean diet improves dyslipidemia and biomarkers in chronic renal failure patients

Dyslipidemia, oxidative stress (OS) and inflammation increase the risk of cardiovascular disease in chronic renal failure (CRF) patients. The aim of this study was to evaluate the effect of nutritional advice on dyslipidemia and biomarkers in CRF patients. 40 CRF patients with dyslipidemia, hypertriglyceridemia and/or hypercholesterolemia were randomly assigned to either the control or the intervention group. The intervention group received nutritional advice adapted to a Mediterranean diet (MD). Patients were assessed at baseline (T0) and after 30 (T1), 60 (T2) and 90 (T3) days for dietary intake and biomarkers. In the intervention group compared to the control group, TG concentrations were decreased by 26% at T3 (p < 0.05), TC concentrations were diminished by 14% at T2 and by 35% at T3 (p < 0.05). A decrease in LDL-C was noted at T2 and T3 (p < 0.05). The TC/HDL-C ratio was diminished at T1, T2 and T3 (p < 0.05). The apo A-I/apo B ratio was elevated at T3 (p < 0.05). HDL-C, apo A-I, apo B concentrations and the TC/LDL-C ratio were similar in the both groups at T1, T2 and T3. Creatinine, urea, glomerular filtration rate (GFR), urate, iron and bilirubin values remained unchanged in both groups. Haemoglobin concentrations were elevated at T1 (p < 0.05). Increased albumin values were observed at T2 (p < 0.05). CRP concentrations were decreased by 29% at T1 (p < 0.05) and 40% (p < 0.01) at T3. Fibrinogen (p < 0.01) concentrations were decreased at T3. In the intervention group compared to control group (p < 0.01), TBARS values were decreased by 16% at T2 and 21% at T3 (p < 0.05). In this study, we demonstrate that the nutritional management of CRF patients before dialysis based on the MD improves food consumption, reduces dyslipidemia and protects against lipid peroxidation and inflammation, allowing patients to enter dialysis with an acceptable nutritional and cardiovascular state.     

Quercetin alleviates activities of intestinal and renal disaccharidases in streptozotocin-induced diabetic rats

Specific activities of both intestinal and renal dissacharidases, such as sucrase, maltase, and lactase, were altered in diabetic rats. Our study was focused to evaluate the effect of feeding quercetin - a bioflavanoid on intestinal and renal dissacharidases in streptozotocin-induced diabetic rats. The rats were fed with 0.1% quercetin in diet. A reduction in intestinal maltase and sucrase, activities in quercetin-fed diabetic rats was observed in contrast to the increased activities in the starch-fed diabetic rats. A significant amelioration in renal dissacharidase activities in quercetin-fed diabetic rats was observed when compared to decreased activity in starch-fed diabetic rats.     

Ochratoxin A at nanomolar concentrations: a signal modulator in renal cells

Ochratoxin A (OTA) is a ubiquitous fungal metabolite with nephrotoxic, carcinogenic, and apoptotic potential. Toxicokinetics make the kidney the primary target organ for OTA. Due to its widespread occurrence in improperly stored foodstuff the complete and safe avoidance of OTA for humans is impossible. There are several reports showing a significant correlation between OTA exposure and certain forms of nephropathies. At nanomolar concentrations OTA leads to specific changes of function and phenotype in renal cells. The toxin interacts with certain cellular "key-molecules" (e. g., mitogen-activated protein (MAP) kinases, Ca2+), thereby disturbing cellular signalling and regulation events as well as mitochondrial function. Moreover, OTA has the ability to modulate physiological signals (e. g., angiotensin II or TNFalpha) and thereby influences cell function and cell growth and may even stable re-program the cells (e. g., altered distribution of chromosomes). This review concentrates on the effects of OTA in the nanomolar range and its interactions with cellular signalling networks in different renal cells proposing OTA to act as a signal modulator.     

Diet therapy of patients with chronic renal failure in its initial stage

The effects of two diets containing different proteins on the time-course of clinical and biochemical characteristics were studied in 60 patients with incipient chronic renal failure. One of the diets included protein of the vegetable origin (85%), whereas the other one animal protein (75%). The diet with vegetable protein produced a beneficial effect on the patients. They stopped making complaints, demonstrating blood pressure and azotemia reduction. The diet with animal protein was a failure. It is desirable that patients with incipient chronic renal failure should receive the first diet on a constant basis as the main treatment regimen.     

Angelica acutiloba root alleviates advanced glycation end-product-mediated renal injury in streptozotocin-diabetic rats

Angelica acutiloba root, a Japanese species of Dong quai being cultivated in Hualien County in eastern Taiwan, is used primarily for gynecological disorders in women. Increasing evidence indicates that advanced glycation end-products (AGEs) contribute to the pathogenesis of diabetic nephropathy. We investigated whether A. acutiloba root is beneficial in the amelioration of AGE-mediated renal injury in a diabetic rat model. Streptozotocin (STZ)-diabetic rats were treated orally with A. acutiloba root extract (AARE) [50, 100, 200 mg/(kg × day)] for 8 wk. Changes in renal function-related parameters in plasma and urine were analyzed at the end of the study. Kidneys were isolated for enzyme immunoassay, pathology histology, immunohistochemistry, and Western blot analyses. Polyphenolic compounds and flavonoids were abundant in AARE. AARE [200 mg/(kg × day)] partially decreased the high plasma glucose level in diabetic rats. Diabetic-dependent alterations in urinary albumin, 24-h urinary albumin excretion rate, creatinine clearance, and glomerular mesangial matrix expansion were ameliorated by AARE treatment. The increased expression of nuclear factor-κB, transforming growth factor-β(1), and the progressive accumulation of fibronectin in kidney of diabetic rats were attenuated by AARE treatment. AARE treatment ameliorated the elevated levels of advanced glycation end products (AGEs) and mitochondrial thiobarbituric acid-reactive substance, as well as the elevated levels of Nε-(carboxymethyl)lysine and receptors for AGEs in kidneys of diabetic rats. The results show that A. acutiloba root has an anti-diabetic property that involves antihyperglycemia accompanied by amelioration of glycation-mediated renal damage.