Maternal Na+ intake induces renal function injury in rats prevented by a short-term angiotensin converting enzyme inhibitor.

The Na+ -ATPase, a secondary pump in the proximal tubule, is only weakly responsive to angiotensin II in adult offspring exposed perinatally to high Na+ intake. We have investigated whether the offspring from mothers given 0.3 mol/L NaCl show an ineffective angiotensin II action to increase in blood pressure. It was hypothesized that functional alterations at adult life are associated with the number of angiotensin II-positive cells in the developing kidney, with increased oxidative stress in maternal/foetal organs, or with morphometrical changes in placentas. Wistar female rats were maintained on 0.3 mol/L NaCl in their drinking water from 20 days before conception until weaning. After weaning, some of the male offspring were treated with enalapril for 21 days. Glomerular filtration rate was recorded up to 210 days of age, when mean arterial pressure was measured after infusion of angiotensin II. To investigate the placenta and foetal kidneys, mothers on tap water or NaCl were also treated with alpha-tocopherol, pregnancy being interrupted on the 20th day. There were no changes in the number of cells positive for angiotensin II in the foetal kidney and unchanged lipid peroxidation in the placenta of offspring exposed to NaCl, but the intermediate trophoblast area in the junctional zone was increased, possibly reducing maternal-foetal exchange. Glomerular filtration rate was reduced and there was an attenuated effect of angiotensin II on elevation of blood pressure, which could be mediated by an elevated angiotensin II during early life, once these disturbances had been prevented by early and short-term treatment with enalapril.

Renal failure due to renal vein thrombosis in a fetus with growth restriction and thrombophilia.

We report a case of renal vein thrombosis diagnosed at 27 weeks of gestation in a dichorionic twin pregnancy. The left kidney of one fetus was hyperechoic and enlarged with echoic streaks following the direction of interlobular veins and the loss of corticomedullary differentiation. In the following weeks, left kidney became smaller and echoic, and Doppler examination showed no flow in both artery and vein. The right kidney had totally normal appearance in the beginning, but it became enlarged and hyperechoic, and progressed into a small echoic kidney with no flow in artery and vein. In the postnatal ultrasound examination, both kidneys appeared hyperechoic with no vascularization in the hilum region. There was thrombosis in arteries and veins of both kidneys, as well as in the inferior vena cava. The investigation for thrombophilia resulted with the combined presence of heterozygote mutation in factor V Leiden and prothrombin 20210 genes.

Biochemical and histological effects of embryonic stem cells in a mouse model of renal failure.

Kidney diseases are a global public health problem. Despite significant advances in the understanding of renal failure (RF) and replacement therapies, this condition carries a series of complications and the life's quality of patients decreases. Differentiation capability of stem cells and their beneficial effects when they are implanted in animal models have been reported. Therefore, this work aimed to induce a long-term RF in mice, evaluating the biochemical and histological effects after implanting mouse embryonic stem cells (mESC). Mice were subjected to renal failure induction (RFI) employing cisplatin, subsequently received intraperitoneal (i.p.) injections of salt solution (control group, n=19) or 50 000 mESC (experimental group, n=19) at 24 hours, 7 days, and 13 days post-RFI. Ten animals in each group were used to analyze functional damage through serum biochemical analysis, and the mortality. For histopathological examination, three animals of each group were sacrificed at 5, 10, and 20 days post-RFI, analyzing the tubular system and glomeruli. Both groups showed blood urea nitrogen (BUN) and creatinine elevation three days post-RFI. Accumulated mortality was lower in the experimental group, presenting statistical significance. Respect to histopathological effects, the control group showed tubular dilatation, segmental focal glomerulosclerosis data, and collapsed glomeruli, while in the experimental group, glomerulosclerosis or collapsed glomeruli were not observed, evidencing regenerative data as characterized by large nuclei with prominent and binucleate nucleoli. In conclusion, mESC implant in mice with RFI significantly decreased the mortality, avoiding a greater histological deterioration related to the disease.

Embryonic pathogenesis of hypogonadism and renal hypoplasia in hgn/hgn rats characterized by male sterility, reduced female fertility and progressive renal insufficiency.

Congenital hypoplasia and dysplasia affect the postnatal development of organs, their physiological functioning in adulthood and the incidence of related diseases at an advanced age. Hypogonadic (hgn/hgn) rats are characterized by male sterility, reduced female fertility, progressive renal insufficiency and growth retardation, all controlled by a single recessive allele (hgn) located on chromosome 10. Since our previous studies indicated that the hypoplasia (dysplasia) of the affected organs was present at birth, we examined the embryonic pathogenesis. We mated hgn/hgn females to Brown Norway males and backcrossed F(1) males to hgn/hgn females. The resulting N(1) fetuses were genotyped using a hgn-linked microsatellite. Both sexes of hgn/hgn fetuses showed low body weight after embryonic day (ED) 15.5 and renal hypoplasia after ED 17.5. Their kidneys contained a reduced number of nephrons in a poorly formed nephrogenic zone and renal cortex. The hgn/hgn ovaries contained a small number of oogonia at ED 15.5 and oocytes after ED 17.5. Testicular growth defects were obvious after ED 17.5, and reduced numbers of Sertoli cells were detected at ED 19.5 and 21.5. The seminiferous cords in hgn/hgn testes contained more apoptotic and mitotic cells than those in +/hgn testes. These findings suggest that the phenotypes described in adult hgn/hgn rats result from embryonic hypogenesis, which continues to early postnatal stage and causes a reduction in functional tissues and cells. Since hgn/hgn rats have an insertion mutation in the microtubule-associated protein Spag5 gene, the embryonic hypogenesis described in hgn/hgn rats might result from defective cell proliferation.

Developmental vascular remodeling defects and postnatal kidney failure in mice lacking Gpr116 (Adgrf5) and Eltd1 (Adgrl4).

GPR116 (ADGRF5) and ELTD1 (ADGRL4) belong to different subfamilies of the adhesion G-protein-coupled receptor group but are both expressed in endothelial cells. We therefore analyzed their functions in mice lacking these receptors. While loss of GPR116 or ELTD1 alone had no obvious effect on cardiovascular or kidney function, mice lacking both, GPR116 and ELTD1, showed malformations of the aortic arch arteries and the cardiac outflow tract leading to perinatal lethality in about 50% of the mutants. In addition to cardiovascular malformations, surviving mice developed renal thrombotic microangiopathy as well as hemolysis and splenomegaly, and their lifespan was significantly reduced. Loss of GPR116 and ELTD1 specifically in endothelial cells or neural crest-derived cells did not recapitulate any of the phenotypes observed in GPR116-ELTD1 double deficient mice, indicating that loss of GPR116 and ELTD1 expressed by other cells accounts for the observed cardiovascular and renal defects.

Embryonic parathyroid rests occur commonly and have implications in the management of secondary hyperparathyroidism.

BACKGROUND: Recurrence after surgery for secondary hyperparathyroidism is not infrequent. Regrowth of the residual parathyroid tissue after subtotal parathyroidectomy or of the autograft after total parathyroidectomy occurs in many cases. Supernumerary glands are also frequently cited as the offending cause and upon revisiting the neck, the surgeon may be surprised that such an obvious gland was 'missed' at the first operation. Indeed, multiple glands removed in sequential operations have been reported suggesting that they develop over time rather than being present from the start. It is possible that microscopic parathyroid 'rests' of embryological origin proliferate under the ongoing stimulus of renal failure to produce supernumerary glands after apparently adequate initial surgery for hyperparathyroidism. The aim of the present study was to determine whether such rests occur frequently or infrequently. METHODS: Operative details and pathology results from 60 consecutive parathyroidectomies were reviewed and the occurrence of parathyroid rests noted. RESULTS: Parathyroid rests were found in 37% of extra parathyroidal tissues submitted for analysis. These rests were found commonly in the thymus. The potential significance of such parathyroid rests undergoing hyperplasia in response to the ongoing stimulus of renal failure and leading to recurrent hyperparathyroidism is discussed. CONCLUSION: Parathyroid rests are common and potentially serve as a cause of recurrent disease in secondary hyperparathyroidism. Consideration should be given to performing thymectomy as part of the treatment of secondary hyperparathyroidism. A more detailed study is warranted.

High-salt diets during pregnancy affected fetal and offspring renal renin-angiotensin system.

Intrauterine environments are related to fetal renal development and postnatal health. Influence of salty diets during pregnancy on renal functions and renin-angiotensin system (RAS) was determined in the ovine fetuses and offspring. Pregnant ewes were fed high-salt diet (HSD) or normal-salt diet (NSD) for 2 months during middle-to-late gestation. Fetal renal functions, plasma hormones, and mRNA and protein expressions of the key elements of renal RAS were measured in the fetuses and offspring. Fetal renal excretion of sodium was increased while urine volume decreased in the HSD group. Fetal blood urea nitrogen was increased, while kidney weight:body weight ratio decreased in the HSD group. The altered ratio was also observed in the offspring aged 15 and 90 days. Maternal and fetal plasma antidiuretic hormone was elevated without changes in plasma renin activity and Ang I levels, while plasma Ang II was decreased. The key elements of local renal RAS, including angiotensinogen, angiotensin converting enzyme (ACE), ACE2, AT1, and AT2 receptor expression in both mRNA and protein, except renin, were altered following maternal high salt intake. The results suggest that high intake of salt during pregnancy affected fetal renal development associated with an altered expression of the renal key elements of RAS, some alterations of fetal origins remained after birth as possible risks in developing renal or cardiovascular diseases.

Application of data mining on the development of a disease distribution map of screened community residents of Taipei county in Taiwan.

This study used data mining techniques to investigate disease forms in various administrative areas and to analyze the differences among various administrative areas in order to further draw up a disease distribution map. It is hoped that may help formulate future public health strategies and to allocate medical resources more appropriately. The major disease forms for residents under the age of 60 were hypertension, hyperglycemia and hyperlipidemia. In regard to the neighboring areas, three neighboring areas, A1, A3, and B9, shared the same disease problems with A4, A5, and B3, while two mountain-area cities, B7 and C10, experienced higher instances of liver function impairment. In terms of the clustering phenomenon among municipally graded administrative areas, the major health problems in Grade A cities were hypertension, hyperglycemia, and hyperlipidemia. The health problems such as liver function impairment and renal dysfunction were more frequently observed in Grade B and Grade C cities.

Evaluation of nephrotoxic effects of mycotoxins, citrinin and patulin, on zebrafish (Danio rerio) embryos.

Citrinin (CTN) and patulin (PAT) are fungal secondary metabolites which are found in food and feed and showed organotoxicity in mature animals. In this study zebrafish embryos were applied to investigate the developmental toxicity of CTN and PAT on embryonic kidney. In the presence of CTN and PAT, the gross morphology of kidneys from embryos with green fluorescent kidney (wt1b:GFP) was not apparently altered. Histological analysis of CTN-treated embryos indicated cystic glomerular and tubular lesions; a disorganized arrangement of renal cells was also found in the PAT-treated group. From the view point of renal function, dextran clearance abilities of embryos exposed to CTN and PAT were significantly reduced. The damaged renal function caused by CTN could be partially rescued by the administration of pentoxifylline, suggesting the reduction of glomerular blood flow contributes to CTN-induced renal dysfunction. Additionally, CTN induced the expression of proinflammation genes, including COX2a, TNF-α and IL-1ß, but failed to modify the levels and distribution of wt1a transcript and Na(+)/K(+)-ATPase protein. In summary, CTN and PAT caused profound nephrotoxicity in histological structure and biological function of zebrafish embryos; the inflammatory pathway and blood rheology may involve in CTN-induced renal impairment.

Glomerular hypertrophy in offspring of subtotally nephrectomized ewes.

We have shown that fetuses whose mothers underwent subtotal nephrectomy (STNx) before pregnancy had high urine flow rates and sodium excretions, but lower hematocrits, plasma chloride, and plasma renin levels compared with controls. To see if these functional differences in utero persist after birth and are the result of altered renal development, we studied 8 lambs born to STNx mothers (STNxL) and 10 controls (ConL) in the second week of life. These lambs were of similar body weights, nose-rump lengths and abdominal girths. Their kidney weights were not different (ConL 36.1 +/- 1.9 vs. STNxL 39.8 +/- 3.3 g), nor were kidney dimensions or glomerular number (ConL 423,520 +/- 22,194 vs. STNxL 429,530 +/- 27,471 glomeruli). However, STNxL had 30% larger glomerular volumes (both mean and total, P < 0.01) and there was a positive relationship between total glomerular volume and urinary protein excretion (P < 0.05) in STNxL. Despite this change in glomerular morphology, glomerular filtration rate, tubular function, urine flow, and sodium excretion rates were not different between STNxL and ConL, nor were plasma electrolytes, osmolality, and plasma renin levels. Thus while many of the functional differences seen in late gestation were not present at 1-2 weeks after birth, the alteration in glomerular size and its relationship to protein excretion suggests that exposure to this altered intrauterine environment may predispose offspring of mothers with renal dysfunction to renal disease in adult life.