Caffeine prevents cognitive impairment induced by chronic psychosocial stress and/or high fat-high carbohydrate diet.

Caffeine alleviates cognitive impairment associated with a variety of health conditions. In this study, we examined the effect of caffeine treatment on chronic stress- and/or high fat-high carbohydrate Western diet (WD)-induced impairment of learning and memory in rats. Chronic psychosocial stress, WD and caffeine (0.3 g/L in drinking water) were simultaneously administered for 3 months to adult male Wistar rats. At the conclusion of the 3 months, and while the previous treatments continued, rats were tested in the radial arm water maze (RAWM) for learning, short-term and long-term memory. This procedure was applied on a daily basis to all animals for 5 consecutive days or until the animal reaches days to criterion (DTC) in the 12th learning trial and memory tests. DTC is the number of days that the animal takes to make zero error in two consecutive days. Chronic stress and/or WD groups caused impaired learning, which was prevented by chronic caffeine administration. In the memory tests, chronic caffeine administration also prevented memory impairment during chronic stress conditions and/or WD. Furthermore, DTC value for caffeine treated stress, WD, and stress/WD groups indicated that caffeine normalizes memory impairment in these groups. These results showed that chronic caffeine administration prevented stress and/or WD-induced impairment of spatial learning and memory.

The nephroprotective effects of pioglitazone and glibenclamide against gentamicin-induced nephrotoxicity in rats: a comparative study.

The aim of the current study is to comparatively examine the nephroprotective effects of pioglitazone and glibenclamide in a rat model subjected to gentamicin-induced nephrotoxicity. Six groups of rats were given either normal saline, or gentamicin, or pioglitazone, or gentamicin plus pioglitazone, or glibenclamide, or gentamicin plus glibenclamide for 11 days. The group administered gentamicin plus glibenclamide had a significant elevation of antioxidant enzyme activity and a significant reduction in lipid peroxidation when compared with the group treated just with gentamicin. The gentamicin plus glibenclamide group also showed mild necrosis according to histopathology when compared with the gentamicin-alone group. In contrast, the gentamicin plus pioglitazone group had a significant reduction in antioxidant enzyme activity and a significant elevation in lipid peroxidation levels when compared with the gentamicin-alone group. Our study showed that only glibenclamide but not pioglitazone has protective effects against gentamicin-induced nephrotoxicity in rats.

Adverse effect of combination of chronic psychosocial stress and high fat diet on hippocampus-dependent memory in rats.

The combined effects of high fat diet (HFD) and chronic stress on the hippocampus-dependent spatial learning and memory were studied in rats using the radial arm water maze (RAWM). Chronic psychosocial stress and/or HFD were simultaneously administered for 3 months to young adult male Wister rats. In the RAWM, rats were subjected to 12 learning trials as well as short-term and long-term memory tests. This procedure was applied on a daily basis until the animal reaches days to criterion (DTC) in the 12th learning trial and in memory tests. DTC is the number of days that the animal takes to make zero error in two consecutive days. Groups were compared based on the number of errors per trial or test as well as on the DTC. Chronic stress, HFD and chronic stress/HFD animal groups showed impaired learning as indicated by committing significantly (P<0.05) more errors than untreated control group in trials 6 through 9 of day 4. In memory tests, chronic stress, HFD and chronic stress/HFD groups showed significantly impaired performance compared to control group. Additionally, the stress/HFD was the only group that showed significantly impaired performance in memory tests on the 5th training day, suggesting more severe memory impairment in that group. Furthermore, DTC value for above groups indicated that chronic stress or HFD, alone, resulted in a mild impairment of spatial memory, but the combination of chronic stress and HFD resulted in a more severe and long-lasting memory impairment. The data indicated that the combination of stress and HFD produced more deleterious effects on hippocampal cognitive function than either chronic stress or HFD alone.

Does the plasma level of vitamins A and E affect acne condition?

BACKGROUND: Vitamin A and E are lipid soluble antioxidants that are necessary for our health. Deficiency in these vitamins can cause serious diseases. Administration of vitamin A and E to patients with acne was shown to improve their acne condition. AIMS: To test the relationship between plasma vitamin A and E levels and acne. METHODS: Plasma vitamin A and E concentrations were determined by high performance liquid chromatography in 100 newly diagnosed untreated patients with acne and were compared with those of 100 age-matched healthy controls. Patients were carefully graded using the Global Acne Grading System. RESULTS: We found that plasma vitamin A concentrations in patients with acne were significantly lower than those of the control group (336.5 vs. 418.1 mug/L, respectively) P = 0.007. We also found that plasma vitamin E concentrations in patients with acne were significantly lower than those of controls (5.4 vs. 5.9 mg/L) P = 0.05. In addition, we found that there is a strong relationship between decrease in plasma vitamin A levels and increase in the severity of acne condition. Patients with severe acne had significantly lower plasma concentrations of vitamins A and E than did those with lower acne grade and the age-matched healthy controls. DISCUSSION: Based on our results, we conclude that low vitamin A and E plasma levels have an important role in the pathogenesis of acne and in the aggravation of this condition.

Factors believed by Jordanian acne patients to affect their acne condition.

This study in Jordan described the pattern of acne in 166 untreated acne patients aged 13-42 years attending dermatology clinics and assessed patients' perceptions of factors that have an effect on their acne condition. Family history of acne was positive in 69.3% of acne patients. Emotional stress, hot weather and sweating were believed to be aggravating factors by acne patients of both sexes, and premenstrual factors and cosmetics were factors among women. Many acne patients believed that their acne was exacerbated by certain aspects of diet including nuts, chocolate, fatty food, fried food, eggs, cakes and biscuits, spices and coffee and tea.

Factors believed by Jordanian acne patients to affect their acne condition

This study in Jordan described the pattern of acne in 166 untreated acne patients aged 13-42 years attending dermatology clinics and assessed patients' perceptions of factors that have an effect on their acne condition. Family history of acne was positive in 69.3% of acne patients. Emotional stress, hot weather and sweating were believed to be aggravating factors by acne patients of both sexes, and premenstrual factors and cosmetics were factors among women. Many acne patients believed that their acne was exacerbated by certain aspects of diet including nuts, chocolate, fatty food, fried food, eggs, cakes and biscuits, spices and coffee and tea

Isolation and characterization of folded fragments released by Staphylococcal aureus proteinase from the non-histone chromosomal protein HMG-1.

HMG-1 was isolated from newborn calf thymus without exposure to overt denaturing conditions. The purified protein was digested under several solvent conditions with the proteinase (endoproteinase GluC) from Staphylococcus aureus strain V8. We found that the preferred site of attack by the enzyme on HMG-1 was influenced markedly by ionic strength and temperature. In 0.35 M NaCl/50 mM Tris-phosphate (pH 7.8) at 37 degrees C, cleavage near the junction between the A and B domains is predominant, as previously reported by Carballo et al. (EMBO J. 2 (1983) 1759-1764). However, in 50 mM Tris-phosphate (pH 7.8) lacking NaCl and at 0 degrees C, cleavage between the B and C domains strongly predominates. Three major products of the digestions were purified and characterized. The fragment consisting of domains B and C was found by circular dichroism to contain a substantial amount of helix. This re-emphasizes the importance of avoiding overt denaturing conditions when working with members of the HMG-1 family.

Analysis of chromatin proteins from human placenta.

Low-salt extracts of chromatin from human term placenta have been examined for the presence of the high mobility group (HMG) proteins. Based upon salt-dissociation characteristics, solubilities in trichloroacetic acid and electrophoretic behaviour on sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and non-equilibrium pH gradient gel electrophoresis (NEPHGE), each of the HMG proteins is present, including HMG-1, -2, -E, -14, and -17. A remarkably large amount of HMG-E is present in term human placenta. Additionally, a protein not previously recognized, which we designate HMG-PL, is present in term placenta. Electrophoretic comparison of the HMG proteins from placentae of varying gestational age, using NEPHGE, demonstrates that all of the placental HMG proteins exhibit multiplicity, reminiscent of chicken erythrocyte HMG proteins. Specifically, we found HMG-E to be unaltered in amounts relative to HMG-1 and -2 in placentae varying from 20 to 40 weeks of gestation. HMG-PL, however, is differentially expressed, increasing in amounts as gestation proceeds past 34 weeks. HMG-PL was purified and subjected to amino acid analysis. Its composition supports the notion that HMG-PL is a member of the HMG-1 family.