Time-dependent beneficial effect of chronic polyphenol treatment with catechin on endothelial dysfunction in aging mice

A controlled redox environment is essential for vascular cell maturation and function. During aging, an imbalance occurs, leading to endothelial dysfunction. We hypothesized that, according to the concept of hormesis, exposure to physiologic oxidative stress during the maturation phase of the endothelium will activate protective pathways involved in stress resistance. C57Bl/6 mice were treated with the polyphenol catechin for the last 3 (post-maturation) or 9 months prior study at 12 months of age. Endothelial dysfunction, assessed by acetylcholine-induced dilations of isolated renal arteries, was present at 12 months (P<0.05). Only the 3-month treatment with catechin fully prevented the decline in efficacy and sensitivity to acetylcholine (P<0.05). Splenocytes adhesion to the native endothelium, expression of CD18 and shedding of CD62L and PSGL-1 augmented in 12 months old mice (P<0.05): only 3-month catechin fully normalized adhesion and prevented the expression of adhesion molecules on splenocytes (P<0.05). Aging was associated with vascular gene alterations, which were prevented by 3-month catechin treatment (P<0.05). In contrast, 9-month catechin further increased COX-2, p22(phox) and reduced MnSOD (P<0.05). In conclusion, we demonstrate a pivotal role of cellular redox equilibrium: exposure to physiologic oxidative stress during the maturation phase of the endothelium is essential for its function.     

Binge inhalation of toluene vapor produces dissociable motor and cognitive dysfunction in water maze tasks

Binge inhalation of toluene, a psychoactive chemical found in many household and industrial products, leads acutely to intoxication with comorbid impairments in motor function and cognitive abilities that appear to recover quickly. Recent evidence, however, indicates that the administration of toluene results in marked changes in neurons of the medial prefrontal cortex that persist for relatively longer periods compared with other brain regions. To elucidate the potential toluene-induced (～5000 ppm) cognitive dysfunctions that continue following the recovery of locomotor abilities, rats were entered into a series of water maze tasks. Following acute toluene intoxication, rats were initially severely impaired in their swimming ability and in their ability to learn and perform a visible platform task. After about 20 min, swimming behavior mostly returned to normal, although cognitive impairments were still evident. Whereas rats with extensive toluene-free training in the maze were able to show normal spatial recall following toluene intoxication, the same acute toluene exposure severely impaired reversal learning, with the rats showing a marked perseveration for the previously learned platform location. Our results indicate that toluene inhalation results in specific cognitive dysfunctions that outlast major impairments in motor abilities, which may be related to impairments in medial prefrontal cortex activity.     

Maroteaux-Lamy syndrome: a case report

The Maroteaux-Lamy disease, or mucopolysaccharidosis type VI is an inherited metabolic disorder severe and rare. It is caused by a deficiency of the enzyme arylsulfatase B. It is characterized by a heterogeneous clinical, radiological and genetic. We report the case of a Maroteaux-Lamy syndrome of in a child aged 7 years whose diagnosis was suspected clinically by the combination of a dysmorphic syndrome, a failure to thrive not harmonious, hepatomegaly and normal intelligence. Radiological exams have objectified dysostosis multiplex. Biochemical analysis of urine showed the abnormal presence of dermatan sulfate. The determination of leukocyte enzyme activity confirmed the diagnosis by showing arylsulfatase B deficiency. Hence the diagnosis of syndrome Maroteaux-Lamy in its mild form (type B) was selected.     

Maternal factors and associated anomalies in NTD fetuses from Tunisia

Aim of the study

To determine the impact of maternal age, consanguinity, season of conception and variation in the amount of amniotic fluid for the appearance of anomalies associated with neural tube defects (NTDs).

Materials and methods

150 NTD fetuses, a result from autopsies (macroscopic autopsy; microscopic study of biopsy fragments; macro and microscopic brain examination), have been examined during a period of three years (01.2006, 01.2009), in the Clinic of Fetopathology, at the Center of Maternity and Neonatology — Tunisia.

Results

Anomalies associated with NTDs occur three times more often in pregnancies with an abnormal amount of amniotic fluid. Also, their likelihood of cardiovascular and reproductive system anomalies is increased four times. Nearly 80% of the NTD fetuses conceived during the autumn-winter period have acrania. Women older than 35, are twice more likely to have underweight children and children with defects of the digestive system and hand. They are also three times more likely to have fetuses with endocrine system abnormalities. Anomalies incompatible with life occur twice as often in consanguineous unions.

Conclusion

The mother’s age, consanguinity, season of conception, and variation in the amount of amniotic fluid have considerable impact on the emergence of associated anomalies in fetuses with NTDs.     

Antioxidant and Antiproliferative Potential of Pearled Barley (Hordeum vulgarae.)

Abstract

Two barley varieties, Falcon and AC Metcalfe, were separated by pearling into seven fractions. Each fraction was subsequently extracted with 80% methanol. Total phenolic content of the extracts so obtained was determined by the Folin-Ciocalteu method and ranged from 0.51 to 6.26 and 0.17 to 4.16 mg ferulic acid equiv/g defatted material, respectively. In both barley varieties, the outermost fraction (F1) yielded the highest phenolic content. The extracts were evaluated for their efficacy in scavenging of peroxyl and hydroxyl radicals using electron paramagnetic resonance (EPR). IC₅₀ value, an indicator of efficacy of a test extract in reducing radical concentration by 50%, ranged from 3.51 to 3.71 mg/mL and 0.27 to 0.51 mg/mL for peroxyl radical for Falcon and AC Metcalfe fraction extracts, respectively. The corresponding values for hydroxyl radical ranged from 0.51 to 3.30 mg/mL and 0.68 to 3.75 mg/mL. Metal chelation activity was determined using the 2,2′-bipyridyl competition assay. Effectiveness of phenolic extracts in inhibiting radical-induced supercoiled DNA breakage was also evaluated. Finally, the potential of phenolic extracts in inhibiting the growth of Caco-2 human adenocarcinoma cells was determined. Barley fractions showed a high level of antiproliferative activity toward inhibition of Caco-2 human colorectal adenocarcinoma cells. Percentage inhibition of cancer cells rendered by Falcon and AC Metcalfe barley fraction extracts ranged from 14% to 74% and 21% to 57%, respectively, at 0.5 mg/mL concentration. The results indicate that barley fractions tested possess significant antioxidant and antiproliferative activities.