Glycosuria in glomerular diseases: histopathology and clinical correlations

There are doubts about the presence of glycosuria and the progress of glomerular disease. Some reports suggest that glycosuria could be an index of a more severe tubulointerstitial lesion. We investigated the presence of glycosuria in 60 patients with primary glomerular diseases: 17 patients (28%) had glycosuria and 43 patients (72%) were glycosuria free. The two groups were similar in age, arterial pressure and sex. Serum creatinine was higher in patients with glycosuria (2.0 ± 1.7 vs 1.3 ± 0.9 mg/dl, P<0.05). The protein excretion rate was 7.5 ± 3.7 vs 5.3 ± 4.2 g/day (P>0.05) in patients with and without glycosuria, respectively, while serum albumin was lower in patients with glycosuria (1.7 ± 0.6 vs 2.7 ± 1.0 g/dl, P<0.05). Several histological forms were present in the group with glycosuria, with membranous glomerulonephritis being the most frequent. Histological evidence of tubular atrophy and interstitial fibrosis prevailed in patients with glycosuria, suggesting a poor prognosis for these patients. We may conclude that the presence of glycosuria in patients with glomerular disease is associated with more pronounced tubular atrophy and interstitial fibrosis and therefore imply a poorer prognosis.

Potentiation of carbon tetrachloride hepatotoxicity by pentosan polysulfate in rats

Few data are available in the literature regarding the effect of pentosan polysulfate (PPS) on normal and fibrotic rat livers. In addition, the combination of PPS and carbon tetrachloride (CCl4) has not been studied so far. The objective of this study was to assess the effect of PPS on rat livers treated or not with CCl4 for the induction of liver fibrosis. The study consisted of four stages: 1) hepatic fibrosis induction with CCl4 (N = 36 rats); 2) evaluation of the effect of PPS on CCl4-induced hepatic fibrosis (N = 36 rats); 3) evaluation of the effect of higher doses of PPS in combination with CCl4 (N = 50 rats); 4) evaluation of the presence of an enzymatic inductor effect by PPS (N = 18 rats) using the sodium pentobarbital test which indirectly evaluates hepatic microsomal enzyme activity in vivo. Adult (60 to 70 days) male Wistar rats weighing 180 to 220 g were used. All animals receiving 0.5 ml 8% CCl4 (N = 36) developed hepatic fibrosis, and after 8 weeks they also developed cirrhosis. No delay or prevention of hepatic fibrosis was observed with the administration of 5 mg/kg PPS (N = 8) and 1 mg/kg PPS (N = 8) 1 h after the administration of CCl4, but the increased hepatotoxicity resulting from the combination of the two substances caused massive hepatic necrosis in most rats (N = 45). PPS (40 mg/kg) alone caused hepatic congestion only after 8 weeks, but massive hepatic necrosis was again observed in association with 0.5 ml CCl4 after 1 to 4 weeks of treatment. Unexpectedly, sleeping time increased with time of PPS administration (1, 2, or 3 weeks). This suggests that PPS does not function as an activator of the hepatic microsomal enzymatic system. Further studies are necessary in order to clarify the unexpected increase in hepatotoxicity caused by the combination of CCl4 and high doses of PPS, which results in massive hepatic necrosis.

Immunohistochemical demonstration of TGF-ß and decorin in paracoccidioidal granulomas

Different patterns of granulomas have been observed in 6- to 8-week-old mice after ip inoculation with 5 x 10(6) yeast cells of Paracoccidioides brasiliensis. Transforming growth factor-ß (TGF-ß) is a cytokine that has been shown to participate in fibrosis and granuloma formation; its activities seem to be modulated by the small proteoglycan decorin. In the present study, TGF-ß and decorin expression in epiploon granulomas was assessed by immunohistochemistry in susceptible (B10.A) and resistant (A/J) mice after 15, 30, 120 and 150 days of P. brasiliensis ip infection. The epiploon was collected, fixed in Methacarn solution and embedded in paraffin, and 5-µm thick sections were used for immunohistochemical analysis employing the streptavidin-biotin-peroxidase technique. The former mouse strain developed fatal disease with many disseminated lesions increasing in size and number during the infection and the latter developed mild disease with the presence of encapsulated granulomas. In the epiploon, TGF-ß was present on macrophages, giant cells, lymphocytes and fibroblasts, and absent on neutrophils. It was also detected in areas of fibrosis and necrosis, as well as disperse in amorphous extracellular matrix, mostly in resistant mice. Decorin was present circumscribing macrophages and giant cells containing fungi, but absent on these cells. In both mouse strains, decorin was found at the periphery of the lesions, and markedly in milky spot granulomas. In resistant mice, positivity was found around fibrotic and necrotic areas of encapsulated and residual lesions containing lysed fungi. Decorin was found associated with thick fibers around encapsulated lesions. In susceptible mice, the size and number of lesions increased with the progression of the disease and were correlated with the weaker expression of decorin. We suggest an association of decorin with the fibrogenic process observed in paracoccidioidal granulomas.

Diagnosis, staging and treatment of hepatocellular carcinoma

Hepatocellular carcinomas are aggressive tumors with a high dissemination power. An early diagnosis of these tumors is of great importance in order to offer the possibility of curative treatment. For an early diagnosis, abdominal ultrasound and serum alpha-fetoprotein determinations at 6-month intervals are suggested for all patients with cirrhosis of the liver, since this disease is considered to be the main risk factor for the development of the neoplasia. Helicoidal computed tomography, magnetic resonance and/or hepatic arteriography are suggested for diagnostic confirmation and tumor staging. The need to obtain a fragment of the focal lesion for cytology and/or histology for a diagnosis of hepatocellular carcinoma depends on the inability of imaging methods to diagnose the lesion. Several classifications are currently available for tumor staging in order to determine patient prognosis. All take into consideration not only the stage of the tumor but also the degree of hepatocellular dysfunction, which is known to be the main factor related to patient survival. Classifications, however, fail to correlate treatment with prognosis and cannot suggest the ideal treatment for each tumor stage. The Barcelona Classification (BCLC) attempts to correlate tumor stage with treatment but requires prospective studies for validation. For single tumors smaller than 5 cm or up to three nodules smaller than 3 cm, surgical resection, liver transplantation and percutaneous treatment may offer good anti-tumoral results, as well as improved patient survival. Embolization or chemoembolization are therapeutic alternatives for patients who do not benefit from curative therapies.

In vivo growth-inhibition of Sarcoma 180 by piplartine and piperine, two alkaloid amides from Piper

Piplartine {5,6-dihydro-1-[1-oxo-3-(3,4,5-trimethoxyphenyl)-2-propenyl]-2(1H)pyridinone} and piperine {1-5-(1,3)-benzodioxol-5-yl)-1-oxo-2,4-pentadienyl]piperidine} are alkaloid amides isolated from Piper. Both have been reported to show cytotoxic activity towards several tumor cell lines. In the present study, the in vivo antitumor activity of these compounds was evaluated in 60 female Swiss mice (N = 10 per group) transplanted with Sarcoma 180. Histopathological and morphological analyses of the tumor and the organs, including liver, spleen, and kidney, were performed in order to evaluate the toxicological aspects of the treatment with these amides. Administration of piplartine or piperine (50 or 100 mg kg-1 day-1 intraperitoneally for 7 days starting 1 day after inoculation) inhibited solid tumor development in mice transplanted with Sarcoma 180 cells. The inhibition rates were 28.7 and 52.3% for piplartine and 55.1 and 56.8% for piperine, after 7 days of treatment, at the lower and higher doses, respectively. The antitumor activity of piplartine was related to inhibition of the tumor proliferation rate, as observed by reduction of Ki67 staining, a nuclear antigen associated with G1, S, G2, and M cell cycle phases, in tumors from treated animals. However, piperine did not inhibit cell proliferation as observed in Ki67 immunohistochemical analysis. Histopathological analysis of liver and kidney showed that both organs were reversibly affected by piplartine and piperine treatment, but in a different way. Piperine was more toxic to the liver, leading to ballooning degeneration of hepatocytes, accompanied by microvesicular steatosis in some areas, than piplartine which, in turn, was more toxic to the kidney, leading to discrete hydropic changes of the proximal tubular and glomerular epithelium and tubular hemorrhage in treated animals.

Modulation of extracellular matrix by nutritional hepatotrophic factors in thioacetamide-induced liver cirrhosis in the rat

Nutritional substances associated to some hormones enhance liver regeneration when injected intraperitoneally, being denominated hepatotrophic factors (HF). Here we verified if a solution of HF (glucose, vitamins, salts, amino acids, glucagon, insulin, and triiodothyronine) can revert liver cirrhosis and how some extracellular matrices are affected. Cirrhosis was induced for 14 weeks in 45 female Wistar rats (200 mg) by intraperitoneal injections of thioacetamide (200 mg/kg). Twenty-five rats received intraperitoneal HF twice a day for 10 days (40 mL·kg-1·day-1) and 20 rats received physiological saline. Fifteen rats were used as control. The HF applied to cirrhotic rats significantly: a) reduced the relative mRNA expression of the genes: Col-α1 (-53%), TIMP-1 (-31.7%), TGF-β1 (-57.7%), and MMP-2 (-41.6%), whereas Plau mRNA remained unchanged; b) reduced GGT (-43.1%), ALT (-17.6%), and AST (-12.2%) serum levels; c) increased liver weight (11.3%), and reduced liver collagen (-37.1%), regenerative nodules size (-22.1%), and fibrous septum thickness. Progranulin protein (immunohistochemistry) and mRNA (in situ hybridization) were found in fibrous septa and areas of bile duct proliferation in cirrhotic livers. Concluding, HF improved the histology and serum biochemistry of liver cirrhosis, with an important reduction of interstitial collagen and increased extracelullar matrix degradation by reducing profibrotic gene expression.

Prognosis of colorectal cancer with liver metastasis: value of a prognostic index

The objective of the present study was to explore the factors related to the prognosis of colorectal cancer (CRC) and to establish a prognostic model for the selection of patients who might benefit from hepatic resection for metastatic CRC. A total of 293 patients undergoing liver resection for metastatic CRC (172 males and 80 females ranging in age from 26 to 80 years) were selected and clinical, pathological and outcome data were examined in this retrospective study. The prognostic index (PI) of the patients was calculated on the basis of results of multivariate analysis. Patients were stratified into different groups, with survival curves projected according to PI. The 1-, 3-, and 5-year overall survival rates were 58.3, 26.4, and 11.3%, respectively. Univariate analysis indicated that degree of primary tumor differentiation, resection margin, preoperative carcinoembryonic antigen (CEA) level, number of liver metastases, and resection of liver metastases were associated with prognosis (P < 0.05). In multivariate analysis, the last three factors were found to be independent prognostic factors. The resection of liver metastases was a favorable factor. Patients were classified into three groups according to PI, which differed significantly in survival rate (P < 0.05). The individual survival rate was evaluated based on PI. Resection of hepatic colorectal metastases may produce long-term survival and cure. The proposed PI was easy to use, was highly predictive of patient outcome, and permitted categorization of patients into treatment groups.

Eccentric and concentric cardiac hypertrophy induced by exercise training: microRNAs and molecular determinants

Among the molecular, biochemical and cellular processes that orchestrate the development of the different phenotypes of cardiac hypertrophy in response to physiological stimuli or pathological insults, the specific contribution of exercise training has recently become appreciated. Physiological cardiac hypertrophy involves complex cardiac remodeling that occurs as an adaptive response to static or dynamic chronic exercise, but the stimuli and molecular mechanisms underlying transduction of the hemodynamic overload into myocardial growth are poorly understood. This review summarizes the physiological stimuli that induce concentric and eccentric physiological hypertrophy, and discusses the molecular mechanisms, sarcomeric organization, and signaling pathway involved, also showing that the cardiac markers of pathological hypertrophy (atrial natriuretic factor, β-myosin heavy chain and α-skeletal actin) are not increased. There is no fibrosis and no cardiac dysfunction in eccentric or concentric hypertrophy induced by exercise training. Therefore, the renin-angiotensin system has been implicated as one of the regulatory mechanisms for the control of cardiac function and structure. Here, we show that the angiotensin II type 1 (AT1) receptor is locally activated in pathological and physiological cardiac hypertrophy, although with exercise training it can be stimulated independently of the involvement of angiotensin II. Recently, microRNAs (miRs) have been investigated as a possible therapeutic approach since they regulate the translation of the target mRNAs involved in cardiac hypertrophy; however, miRs in relation to physiological hypertrophy have not been extensively investigated. We summarize here profiling studies that have examined miRs in pathological and physiological cardiac hypertrophy. An understanding of physiological cardiac remodeling may provide a strategy to improve ventricular function in cardiac dysfunction.

In vitro proliferation and differentiation of hepatic oval cells and their potential capacity for intrahepatic transplantation

Hepatic oval cells (HOCs) are recognized as facultative liver progenitor cells that play a role in liver regeneration after acute liver injury. Here, we investigated the in vitro proliferation and differentiation characteristics of HOCs in order to explore their potential capacity for intrahepatic transplantation. Clusters or scattered HOCs were detected in the portal area and interlobular bile duct in the liver of rats subjected to the modified 2-acetylaminofluorene and partial hepatectomy method. Isolated HOCs were positive for c-kit and CD90 staining (99.8% and 88.8%, respectively), and negative for CD34 staining (3.6%) as shown by immunostaining and flow cytometric analysis. In addition, HOCs could be differentiated into hepatocytes and bile duct epithelial cells after leukemia inhibitory factor deprivation. A two-cuff technique was used for orthotopic liver transplantation, and HOCs were subsequently transplanted into recipients. Biochemical indicators of liver function were assessed 4 weeks after transplantation. HOC transplantation significantly prolonged the median survival time and improved the liver function of rats receiving HOCs compared to controls (P=0.003, Studentt-test). Administration of HOCs to rats also receiving liver transplantation significantly reduced acute allograft rejection compared to control liver transplant rats 3 weeks following transplantation (rejection activity index score: control=6.3±0.9; HOC=3.5±1.5; P=0.005). These results indicate that HOCs may be useful in therapeutic liver regeneration after orthotopic liver transplantation.

Streptozotocin-induced diabetes mellitus affects lysosomal enzymes in rat liver

It has been previously shown that dextran sulfate administered to diabetic rats accumulates in the liver and kidney, and this could be due to a malfunction of the lysosomal digestive pathway. The aim of the present study was to evaluate the expression and activities of lysosomal enzymes that act upon proteins and sulfated polysaccharides in the livers of diabetic rats. Diabetes mellitus was induced by streptozotocin in 26 male Wistar rats (12 weeks old), while 26 age-matched controls received only vehicle. The livers were removed on either the 10th or the 30th day of the disease, weighed, and used to evaluate the activity, expression, and localization of lysosomal enzymes. A 50-60% decrease in the specific activities of cysteine proteases, especially cathepsin B, was observed in streptozotocin-induced diabetes mellitus. Expression (mRNA) of cathepsins B and L was also decreased on the 10th, but not on the 30th day. Sulfatase decreased 30% on the 30th day, while glycosidases did not vary (or presented a transitory and slight decrease). There were no apparent changes in liver morphology, and immunohistochemistry revealed the presence of cathepsin B in hepatocyte granules. The decrease in sulfatase could be responsible for the dextran sulfate build-up in the diabetic liver, since the action of sulfatase precedes glycosidases in the digestive pathway of sulfated polysaccharides. Our findings suggest that the decreased activities of cathepsins resulted from decreased expression of their genes, and not from general lysosomal failure, because the levels of glycosidases were normal in the diabetic liver.

Assessment of indicators of vitamin A status in non-cirrhotic chronic hepatitis C patients

Subjects with chronic liver disease are susceptible to hypovitaminosis A due to several factors. Therefore, identifying patients with vitamin deficiency and a requirement for vitamin supplementation is important. Most studies assessing vitamin A in the context of hepatic disorders are conducted using cirrhotic patients. A cross-sectional study was conducted in 43 non-cirrhotic patients with chronic hepatitis C to evaluate markers of vitamin A status represented by serum retinol, liver retinol, and serum retinol-binding protein levels. We also performed the relative dose-response test, which provides an indirect estimate of hepatic vitamin A reserves. These vitamin A indicators were assessed according to the stage of liver fibrosis using the METAVIR score and the body mass index. The sample study was predominantly composed of male subjects (63%) with mild liver fibrosis (F1). The relative dose-response test was <20% in all subjects, indicating vitamin A sufficiency. Overweight or obese patients had higher serum retinol levels than those with a normal body mass index (2.6 and 1.9 µmol/L, respectively; P<0.01). Subjects with moderate liver fibrosis (F2) showed lower levels of serum retinol (1.9 vs 2.5 µmol/L, P=0.01) and retinol-binding protein levels compared with those with mild fibrosis (F1) (46.3 vs 67.7 µg/mL, P<0.01). These results suggested an effect of being overweight on serum retinol levels. Furthermore, more advanced stages of liver fibrosis were related to a decrease in serum vitamin A levels.

Comparison between the availability of iron in the presence of vitamin a and β-carotene in foods and medications

The objective of this work was to verify the availability of iron in the presence of vitamin A as components of foods and in combinations with medicines. The iron available was measured in the presence of vitamin A in foods - common bean (B), beef liver (Li) and carrot (C) - and medicines - Fer-In-Sol® (Fer) (Mead Johnson), Arovit® (A) (Roche) and Neutrofer® (N) (Sigma Pharma) - as well as in combinations of both. β-carotene, vitamin A, total iron, heme and non heme iron, percentage of dialyzable iron and amount of dialyzable iron was determined. Vitamin A and β-carotene had a positive effect on the percentage of iron dialysis. Carrot and liver had a better percentage of dialyzable iron than their respective medicine at similar concentrations. Therefore, we can conclude that there has been an influence of vitamin A over the dialysis of iron, being the mixtures containing liver the ones which achieved the highest concentrations of dialyzable iron, and also that, according to the amounts needed to obtain the daily recommended intake of iron, they are good for consumption.