Cereal Chem. 77(4): [445][446][447] Starch was extracted and cleaned from 99 accessions of 20 species of Aegilops and also from 200 accessions of hexaploid wheat. Amylose content was determined by iodine staining and absorbance at 535 and 620 nm. Particle-size distribution was determined by laser scattering. The amylose content of the Aegilops accessions did not exceed the extremes found in domesticated wheat. Aegilops species, on the whole, had a lower content of small particles than the hexaploid wheats. There was no correlation between amylose content and particle-size distribution. Some species of Aegilops may be useful sources of low-starch B-type granules for hexaploid wheat, if the trait can be transferred, but they are unlikely to contribute to further variation in amylose content.Publication no. C-2000-0601-07R.

Obesity is a contemporary health problem of rapidly increasing prevalence. One possible cause of obesity is loss of control over consumption of highly palatable foodstuffs, perhaps mirroring the processes involved in drug addiction. Accordingly, the striatum may be a key neural substrate involved in both food and drug craving. We hypothesised here that prolonged exposure to 10% sucrose solution might cause neuroadaptations in the striatum that are analogous to those previously reported following prolonged exposure to alcohol or recreational drugs. Male Wistar rats were given constant access to 10% sucrose solution (in addition to normal lab chow and tap water) for 8 months and were compared with control rats receiving no sucrose access. Rats in the sucrose group typically drank more than 100 ml of sucrose solution per day and showed 13% greater body weight than controls at the end of the 8 months. Striatal dopamine (DA) concentrations were decreased in the sucrose group rats relative to controls. Differential expression of 18 proteins was identified in the striatum of the sucrose group rats relative to controls. Down regulated proteins included pyridoxal phosphate phosphatase, involved in DA synthesis, and glutathione transferase, involved in free radical scavenging. Up regulated proteins included prolactin (which is under negative regulation by DA) and adipose differentiation-related protein, involved in fat synthesis. We hypothesise that DA-related neuroadaptations in the striatum caused by prolonged sucrose intake may partly drive compulsive intake and seeking of high palatability foodstuffs, in a similar way to that observed with drug and alcohol addictions.

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Selective serotonin reuptake inhibitors (SSRIs) are commonly recognized as the pharmacological treatment of choice for patients with depressive disorders, yet their use in adolescent populations has come under scrutiny following reports of minimal efficacy and an increased risk of suicidal ideation and behavior in this age group. The biological mechanisms underlying these effects are largely unknown. Accordingly, the current study examined changes in hippocampal protein expression following chronic administration of paroxetine in drinking water (target dose = 10 mg/kg for 22 days) to adult and adolescent rats. Results indicated age-specific changes in protein expression, with paroxetine significantly altering expression of 8 proteins in adolescents only and 10 proteins solely in adults. A further 12 proteins were significantly altered in both adolescents and adults. In adults, protein changes were generally suggestive of a neurotrophic and neuroprotective effect of paroxetine, with significant downregulation of apoptotic proteins Galectin 7 and Cathepsin B, and upregulation of the neurotrophic factor Neurogenin 1 and the antioxidant proteins Aldose reductase and Carbonyl reductase 3. Phosphodiesterase 10A, a signaling protein associated with major depressive disorder, was also downregulated (-6.5-fold) in adult rats. Adolescent rats failed to show the neurotrophic and neuroprotective effects observed in adults, instead displaying upregulation of the proapoptotic protein BH3-interacting domain death agonist (4.3-fold). Adolescent protein expression profiles also suggested impaired phosphoinositide signaling (Protein kinase C: -3.1-fold) and altered neurotransmitter transport and release (Syntaxin 7: 5.7-fold; Dynamin 1: -6.9-fold). The results of the present study provide clues as to possible mechanisms underlying the atypical response of human adolescents to paroxetine treatment.

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