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Biomedical subjects

E Rocchi

Publications and source records attributed to E Rocchi.

18 recordsLinked to original sources

Regulation of transferrin, transferrin receptor, and ferritin genes in human duodenum.

To gain insights at the molecular level into the expression of iron-regulated genes [transferrin (Tf), transferrin receptor (TfR), and ferritin H and L subunits] in human intestinal areas relevant to iron absorption, the steady-state levels of specific messenger RNAs (mRNAs) were analyzed in gastric and duodenal samples obtained from 6 normal subjects, or 10 patients with anemia, 14 patients with untreated iron overload, and 8 patients with various gastrointestinal disorders. No Tf mRNA was detected in human gastroduodenal tissue, confirming earlier findings in the rat. In normal subjects, although higher levels of ferritin H- and L-subunit mRNAs were consistently found in duodenal than in gastric samples, no differences in the content of TfR transcripts were detected. However, a dramatic increase in TfR mRNA levels was specifically found in duodenal samples from subjects with mild iron deficiency but severe anemia. This response of the TfR gene is presumably secondary to decreased cellular iron content due to its accelerated transfer into the bloodstream, as also indicated by the low levels of ferritin subunit mRNAs found in the same tissue samples, and is not linked to faster growth rate of mucosal cells because no changes in duodenal expression of histone, a growth-related gene, were detected. In patients with secondary iron overload, a down-regulation of duodenal TfR gene expression and a concomitant increase in ferritin mRNA content were documented. On the contrary, a lack of TfR gene down-regulation and an abnormally low accumulation of ferritin H- and L-subunit mRNAs were detected in the duodenums of subjects with idiopathic hemochromatosis. Whether these molecular abnormalities in idiopathic hemochromatosis are relevant to the metabolic defect(s) of the disease is presently unknown.

Adult

[The clinical implications of the use of an amino acid mixture without tryptophan in liver cirrhosis].

The ingestion of an amino acid mixture lacking tryptophan causes a rapid fall of plasma tryptophan in healthy subjects. This is because amino acids elicit protein synthesis and endogenous tryptophan is incorporated into new proteins. If protein synthesis is the mechanism through which tryptophan-free solution decrease blood tryptophan, it may be interesting to study tryptophan levels after a tryptophan-free mixture in subjects with impaired protein synthesis. In the present paper we show that in 27 cirrhotics the administration of a tryptophan-free solution caused a fall of total plasma tryptophan that began significantly later than in 14 control subjects, the delay being significantly proportional to the severity of the disease. The difference between control and cirrhotic subjects was due to the bound fraction of plasma tryptophan. The diagnostic and clinical usefulness of our findings are discussed.

Amino Acids

Decrease in plasma tryptophan after a tryptophan-free amino acid solution. A comparison between cirrhotic and control subjects.

In healthy subjects the administration of an amino acid mixture devoid of tryptophan causes a marked decrease of plasma tryptophan. This is because amino acid mixtures induce protein synthesis and tryptophan in blood is incorporated into newly synthesized proteins. We hypothesized that a tryptophan-free mixture could differently affect plasma tryptophan levels in subjects with an impaired protein synthesis such as chronic liver patients. We studied tryptophan levels after a tryptophan-free amino acid solution in controls and cirrhotics fasting 12 hours. Plasma total tryptophan fell to 91% of the initial level 60 minutes after the administration of the diet, to 71% after 120, and to 50% after 210' in controls. In cirrhotics the solution caused a decrease of plasma tryptophan that began significantly later than in controls, the delay being proportional to the severity of the disease. Cirrhotics were subdivided into two groups in accordance to the Pugh modification of the Child-Turcotte criteria. Total plasma tryptophan was 100% of base line levels after 60', 88% after 120', and 65% after 210' in less severe clinical condition; total plasma tryptophan was 102% of base line levels after 60', 98% after 120', and 75% after 210' in more severe clinical condition.

Adult

Liver iron overload and desferrioxamine treatment of porphyria cutanea tarda.

The aim of this paper is to evaluate invasive and non-invasive indices of iron store and compare the effectiveness of different ferrodepletive protocols in 150 patients with porphyria cutanea tarda (PCT). Iron removal was performed either by intensive phlebotomy (22 cases) or slow subcutaneous and high intravenous doses of desferrioxamine (18 and 5 cases, respectively), and several laboratory parameters were studied; among these, oligo-elements and urinary porphyrins (detected by HPLC) were taken into account before and after the treatments. Serum iron, transferrin saturation, ferritin (RIA) and nuclear magnetic resonance results were compared with invasive findings in order to detect the metal deposition in liver tissue (atomic absorption concentration, optic or electron-microscopic detection). Liver iron overload was observed in 95% of cases. Full normalization of the disease took place by all the treatments, even if it required slightly more time in the phlebotomy group. We may conclude that ferrodepletive treatments are highly effective in PCT and, considering the fact that siderosis and liver damage always accompany the disease, these treatments are proposed as first choice in such cases.

Bloodletting

Carotenoids and liposoluble vitamins in liver cirrhosis.

The role played by carotenoids, retinol and tocopherol in quencing oxidative cellular damage and combatting tumor growth is well documented, but little is known about their activity in human liver cirrhosis (LC), where oxidative damage and tumoral complications are common-place. We investigated 59 patients with LC of different etiology on admission to hospital and compared them with 32 healthy controls, matched for age and sex. Nutritional (cutaneous skinfolds, creatinine-height index) and serum parameters were determined; of these, alpha- and beta-carotene, cryptoxanthin, lycopene, retinol and alpha-tocopherol were detected by an high-performance liquid chromatographic (HPLC) technique, devised in our laboratory, which afforded an accurate and simultaneous resolution of all six compounds. The results point to a significant reduction in almost all the vitamin factors in LC, as well as in total serum lipids. In consequence, the ratio tocopherol/total serum lipids remains almost unchanged: 2.45 +/- 0.08 (m +/- se) in controls and 2.34 +/- 0.16 in patients. The effects of age, sex, nutritional habits, alcohol, malnutrition and the severity of the disease were also evaluated in relation to the vitamin-factor levels. It is suggested that the reduced levels observed in LC patients are due to a number of factors including portal hypertension and lymphatic circulation impairment, and it is concluded that thorough screening and improved diet are beneficial in the follow-up of LC.

Carotenoids

Regulation of hepatic transferrin, transferrin receptor and ferritin genes in human siderosis.

Although many studies have examined the regulation of transferrin, transferrin receptor and ferritin subunit gene expression in experimental systems, no molecular biological data in humans have been documented to date. In this study we simultaneously analyzed the hepatic content of transferrin, transferrin receptor and heavy and light ferritin subunit messenger RNAs in tissue samples obtained from subjects with normal iron balance and patients with primary or secondary iron overload. Steady-state levels of transferrin messenger RNA were not depressed by iron overload. On the contrary, they were increased (p less than 0.001) in patients with severe hepatic siderosis (liver iron content greater than 200 mumol/gm dry wt) as compared with the control group. This indicates that, as already suggested by our previous data in experimental siderosis, iron maintains the ability to induce transferrin gene activity even when cellular iron content is significantly increased. Transferrin receptor gene expression was found to respond in the same manner to any cause of iron-tissue load, regardless of the cause. In fact, a lower signal for transferrin receptor messenger RNA was consistently detected in iron-overloaded patients vs. control subjects, particularly in patients with thalassemia major and idiopathic hemochromatosis (p less than 0.001). Ferritin light-subunit messenger RNA accumulation was significantly increased in those patients with severe siderosis (idiopathic hemochromatosis and thalassemia major = liver iron between 200 and 600 mumol/gm dry wt). The fact that no significant change in hepatic ferritin heavy-subunit gene expression was detected in iron-loaded patients confirms preferential production of light-subunit--enriched ferritins in long-term iron overload.(ABSTRACT TRUNCATED AT 250 WORDS)

Female

Liver gene expression during chronic dietary iron overload in rats.

To clarify the pathogenesis of hepatic iron toxicity, we investigated the effect of chronic dietary iron overload on the expression of several genes in rat liver. After 10 wk of iron treatment, when only minor histological features of liver damage were appreciable, the level of pro-alpha 2(I)-collagen mRNA was already higher than in control liver and increased further at 30 wk of treatment. Also, the relative amount of L ferritin subunit mRNA was enhanced early by iron load and was even more elevated at the latest time point considered, whereas neither H ferritin subunit nor transferrin mRNA levels were affected by iron treatment. In contrast, after chronic iron treatment, no variations were found in the steady-state level of mRNAs transcribed from liver-specific and preferentially expressed genes (albumin, alpha-fetoprotein, apolipoprotein A-1), growth-related genes (c-myc, c-Ha-ras and c-fos) and stress-induced genes (heat shock protein 70). These results suggest that chronic dietary iron overload in rats can specifically activate target genes in the liver (i.e., L ferritin and procollagen) in the absence of either histological signs of severe liver damage or alterations in differentiated liver functions.

Animals

High weekly intravenous doses of desferrioxamine in porphyria cutanea tarda.

Two elderly patients with sporadic porphyria cutanea tarda (PCT) and severe associated diseases were treated with high weekly intravenous doses of desferrioxamine. This therapy proved more effective than slow subcutaneous desferrioxamine infusion and no adverse effect was recorded. We consider high dose intravenous desferrioxamine a suitable treatment for those PCT patients with severe associated diseases who are unable to apply the technique of subcutaneous desferrioxamine infusion.

Aged

Iron removal therapy in porphyria cutanea tarda: phlebotomy versus slow subcutaneous desferrioxamine infusion.

Twenty-five patients with overt clinical and biochemical findings of porphyria cutanea tarda took part in a study comparing intensive phlebotomy with slow subcutaneous desferrioxamine treatment. Fifteen male patients (Group A) had intensive venesection therapy. Ten patients (Group B) with associated diseases (minor thalassemia, cardiovascular impairment, pulmonary tuberculosis or severe liver cirrhosis) received 1.5 g of desferrioxamine by slow subcutaneous infusion using an automatic syringe pump 5 days a week. No patient complained of appreciable side effects. Serum iron, ferritin and uroporphyrins were normalized in all subjects by the end of treatment. The mean time necessary for complete recovery was 13.8 months (range 9-19) and 11.2 months (range 6-14) in Groups A and B, respectively. Liver function significantly improved during and after the treatments in both groups. We conclude that recovery from porphyria cutanea tarda can be achieved equally well using phlebotomy or desferrioxamine subcutaneous infusion. Phlebotomy is easily performed and remains the treatment of choice; slow subcutaneous desferrioxamine treatment, although expensive, is recommended when severe associated diseases contra-indicate venesection.

Adult

Hepatitis B virus infection in porphyria cutanea tarda.

Serum markers of hepatitis B virus (HBV) infection were determined in 82 patients with porphyria cutanea tarda (PCT). Pathogenetic factors (alcohol, thalassemia minor, drugs) and clinical and histologic findings of PCT were taken into account. The prevalence of HBV infection was very high (70.7%). Hepatitis B surface antigen (HBsAg) was positive in 14 patients (17%). Eight patients had HBV infection as the only documented acquired factor. The clinical picture and histologic findings were aggravated by HBV infection; primary hepatic carcinoma occurred in four patients with HBV infection. Liver siderosis was histologically documented in 82.6% of cases, serum ferritin was pathologically increased in 91%, confirming the role of iron overload in PCT. A correlation (p less than 0.02; chi-squared method) was found between increased serum ferritin levels and HBV infection, suggesting a possible relationship between liver siderosis and HBV clearance. HBV infection appears to be a relevant additional factor in the pathogenesis of PCT liver disease.

Adult

Serum ferritin in the assessment of liver iron overload and iron removal therapy in porphyria cutanea tarda.

Serum ferritin, an index of iron stores, was studied in 60 patients with porphyria cutanea tarda (PCT), in 21 patients who had other liver diseases without siderosis (cirrhosis [LC] and chronic active hepatitis [CAH]), and in 32 patients with associated liver siderosis (alcoholic LC, LC and CAH in minor thalassemia). Ferritin levels were higher in patients with porphyria than in healthy controls and patients without liver siderosis (P less than 0.001), whereas no statistical difference was observed between patients with porphyria and those with liver siderosis. Because iron removal is considered the treatment of choice for PCT, some patients with PCT underwent phlebotomy and others received chelating therapy with subcutaneous infusion of deferoxamine. Follow-up of the patients showed a correlation between serum ferritin level and urinary porphyrin excretion; when the clinical and biochemical syndrome became normal, serum iron and ferritin had fallen to normal values (t test pair data analysis before and after: P less than 0.001 in each group). No appreciable difference was found between controls and patients with PCT whose conditions had been normalized, irrespective of the chronic liver damage always present in PCT. Our results suggest that serum ferritin increase in PCT is related more to liver iron overload than to liver damage, and ferritin follow-up is recommended to indicate the exhaustion of hepatic iron stores during iron depletion therapy, as well as to detect an early replenishment after remission.

Adult

Safety of valproate in porphyria cutanea tarda.

Treatment of epileptic seizures in patients with hepatic porphyrias is a challenging problem due to enzymatic induction activity of phenobarbital (PB), phenytoin (PHT), carbamazepine (CBZ), and clonazepam (CZP). We present the case of a patient with partial seizures treated with PHT and showing clinical signs and biochemical abnormalities of porphyria cutanea tarda (PCT). We withdrew PHT and treated the patient with sodium valproate (VPA). We followed the patient for 6 months during VPA therapy. During this period, clinical signs of PCT disappeared and biochemical values normalized. Our study shows that VPA is a safe treatment in epileptic patients with PCT.

Aged

Standard or branched-chain amino acid infusions as short-term nutritional support in liver cirrhosis?

The metabolic effects of selected and branched-chain amino acid (BCAA)-enriched parenteral solutions were studied in liver cirrhosis. After 3 days of an oral protein-free diet with balanced amino acid (AA) infusion, 36 cirrhotic patients without encephalopathy were randomly divided into four groups. Groups A and B were infused for 5 days with BCAA (valine, leucine, isoleucine) at doses of 0.5 and 1.0 g/kg/day, respectively, as the only nitrogen source. Group C received 0.8 g/kg of essential and nonessential AA solution with a prevalence of BCAA; the last group (D) continued the basic standard diet, as control. Routine chemistry, urinary nitrogen losses, nitrogen balance, and the whole plasma AA pattern were detected before and after the treatment period. BCAA alone led to an impressive and significant improvement in the basic AA pattern in both the A and B groups. The same results were obtained in group C for plasma AA. In particular, the ratio of BCAA to aromatic amino acids in groups A, B, and C was significantly increased (p less than 0.01, less than 0.02, less than 0.02, respectively). In group D the AA pattern and the BCAA/aromatic amino acid ratio remained unchanged. The negative nitrogen balance of the base state remained unchanged after 0.5 g of BCAA (A); it improved significantly and became positive during and after the infusions of a double dose of BCAA (B), as it did in the case of selective solutions (C), although to a lesser extent; the negative nitrogen balance of the control group showed only a slight improvement.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids