CLytA-DAAO Chimeric Enzyme Bound to Magnetic Nanoparticles. A New Therapeutical Approach for Cancer Patients?

D-amino acid oxidase (DAAO) is an enzyme that catalyzes the oxidation of D-amino acids generating H2O2. The enzymatic chimera formed by DAAO bound to the choline-binding domain of N-acetylmuramoyl-L-alanine amidase (CLytA) induces cytotoxicity in several pancreatic and colorectal carcinoma and glioblastoma cell models. In the current work, we determined whether the effect of CLytA-DAAO immobilized in magnetic nanoparticles, gold nanoparticles, and alginate capsules offered some advantages as compared to the free CLytA-DAAO. Results indicate that the immobilization of CLytA-DAAO in magnetic nanoparticles increases the stability of the enzyme, extending its time of action. Besides, we compared the effect induced by CLytA-DAAO with the direct addition of hydrogen peroxide, demonstrating that the progressive generation of reactive oxygen species by CLytA-DAAO is more effective in inducing cytotoxicity than the direct addition of H2O2. Furthermore, a pilot study has been initiated in biopsies obtained from pancreatic and colorectal carcinoma and glioblastoma patients to evaluate the expression of the main genes involved in resistance to CLytA-DAAO cytotoxicity. Based on our findings, we propose that CLytA-DAAO immobilized in magnetic nanoparticles could be effective in a high percentage of patients and, therefore, be used as an anti-cancer therapy for pancreatic and colorectal carcinoma and glioblastoma.

Sodium benzoate for the treatment of behavioral and psychological symptoms of dementia (BPSD): A randomized, double-blind, placebo-controlled, 6-week trial.

OBJECTIVE: Sodium benzoate, a D-amino acid oxidase (DAAO) inhibitor, improved cognitive function of early-phase Alzheimer's disease (AD) after 24-week treatment. This study examined benzoate treatment for behavioral and psychological symptoms of dementia (BPSD). METHODS: In a double-blind, 6-week trial, 97 patients with BPSD were randomized to receive placebo or benzoate (mean dose: 622.0 mg/day). The primary outcomes were ADAS-cog and BEHAVE-AD. RESULTS: Two treatments showed similar safety and primary and secondary outcomes. CONCLUSIONS: Compared to antecedent 24-week, higher-dose treatment for early-phase AD, benzoate appeared ineffective in this 6-week trial. Longer-duration, higher-dose trials are warranted to clarify its efficacy for BPSD.

Influence of acute and chronic administration of benzylamine on glucose tolerance in diabetic and obese mice fed on very high-fat diet

The combination of vanadate plus benzylamine has been reported to stimulateglucose transport in rodent adipocytes and to mimic other insulin actions in diversestudies. However, benzylamine alone activates glucose uptake in human fat cells andincreases glucose tolerance in rabbits. The aim of this work was to unravel the benzylamineantihyperglycemic action and to test whether its chronic oral administrationcould restore the defective glucose handling of mice rendered slightly obese anddiabetic by very high-fat diet (VHFD). When VHFD mice were i.p. injected withbenzylamine at 0.7 to 700 ìmol/kg before glucose tolerance test, they exhibitedreduced hyperglycemic response without alteration of insulin secretion. Whole bodyglucose turnover, as assessed by the glucose isotopic dilution technique, wasunchanged in mice perfused with benzylamine (total dose of 75 ìmol/kg). However,their in vivo glycogen synthesis rate was increased. Benzylamine appeared thereforeto directly facilitate glucose utilisation in peripheral tissues. When given chronicallyat 2000 or 4000 ìmol/kg/d in drinking water, benzylamine elicited a slightreduction of water consumption but did not change body weight or adiposity anddid not modify oxidative stress markers. Benzylamine treatment improved glucosa tolerance but failed to normalize the elevated glucose fasting plasma levels of VHFDmice. There was no influence of benzylamine ingestion on lipolytic activity, basal andinsulin-stimulated glucose uptake, and on inflammatory adipokine expression inadipocytes. The improvement of glucose tolerance and the lack of adverse effects onadipocyte metabolism, reported here in VHFD mice allow to consider orally givenbenzylamine as a potential antidiabetic strategy which deserves to be further studied in other diabetic models (AU)

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Resultados preliminares no emprêgo da D-4 amino-3 isoxazolidinone no tratamento de três casos lepromatosos (Nota prévia) / Preliminary results in the use of D 4-amino-3 isoxazolidinone the treatment of three cases lepromatous (Foreword)

A preliminary report is given about cycloserine in leprosy. There lepromatous patientswere treated with doses of 500 and 750 mg. a day of cycloseine during two months. A clinical improvement was noted without lepra reaction, but definitive conclusions must wait a longer time of cycloserine therapy.