Inhibition of protein glycation by essential oils of branchlets and fruits of Juniperus communis subsp. hemisphaerica.

Oxidative stress and protein glycation play pivotal roles in the pathophysiology of diabetes mellitus and its vascular complications. The present study aimed to investigate the anti-glycation properties of essential oils obtained from different parts of Juniperus communis subsp. hemisphaerica. The branchlets of male tree (BMT) and branchlets of female (BFT) tree, and fruits of J. communis subsp. hemisphaerica were extracted using steam distillation method. The oils were phytochemically analyzed using gas chromatography-mass spectrometry. Anti-glycation properties were evaluated using hemoglobin and insulin glycation assays. Overall, 18 volatile components were identified in the J. communis subsp. hemisphaerica oils, amounting to 82.1%, 100.0% and 96.4% of the BMT, BFT and fruit oils, respectively. Promising inhibitory activity was observed from all concentrations of the tested oils in the hemoglobin and insulin glycation assays. The inhibitory activities peaked to 89.9% (BFT oil; 200 µg mL(-1)) and 81.0% (BFT oil; 600 µg mL(-1)) in the hemoglobin and insulin glycation assays, respectively. The evidence from this study suggests that essential oils obtained from the fruits and branchlets of J. communis subsp. hemisphaerica possess anti-glycation properties. These activities may find implication for the prevention and treatment of diabetic complications.

Antioxidant activities of Juniperus foetidissima essential oils against several oxidative systems

The present study aimed to evaluate the antioxidant activity of essential oils obtained from branchlets of male and female trees as well as fruits of Juniperus foetidissima Willd., Cupressaceae, from Iran. For this purpose, essential oils of J. foetidissima were phytochemically analyzed and different concentrations of them were tested in five oxidative systems: 1) low-density lipoprotein oxidation; 2) linoleic acid peroxidation; 3) red blood cell hemolysis; 4) hemoglobin glycation; and 5) insulin glycation assays. In all employed systems, antioxidant effects were observed from the three tested oils though in varying degrees. The most promising activities of the oils were observed against hemoglobin and insulin glycation. Antioxidant activities of the oils did not appear to be dose-dependent. In addition, no consistent superiority in antioxidant effects was observed from a single oil in different assays. In view of the current results, J. foetidissima branchlet and fruit oils could be regarded as effective natural products with anti-glycation activity.

Mitochondrial DNA and Y-chromosome variation in the caucasus.

We have analyzed mtDNA HVI sequences and Y chromosome haplogroups based on 11 binary markers in 371 individuals, from 11 populations in the Caucasus and the neighbouring countries of Turkey and Iran. Y chromosome haplogroup diversity in the Caucasus was almost as high as in Central Asia and the Near East, and significantly higher than in Europe. More than 27% of the variance in Y-haplogroups can be attributed to differences between populations, whereas mtDNA showed much lower heterogeneity between populations (less then 5%), suggesting a strong influence of patrilocal social structure. Several groups from the highland region of the Caucasus exhibited low diversity and high differentiation for either or both genetic systems, reflecting enhanced genetic drift in these small, isolated populations. Overall, the Caucasus groups showed greater similarity with West Asian than with European groups for both genetic systems, although this similarity was much more pronounced for the Y chromosome than for mtDNA, suggesting that male-mediated migrations from West Asia have influenced the genetic structure of Caucasus populations.

The effect of fasting in Ramadan on the values and interrelations between biochemical, coagulation and hematological factors.

BACKGROUND: The possible consequences of the long intermittent fasting schedule during Ramadan (one month of food and water intake limited to night hours, a practice that is followed by the majority of the Muslims worldwide) on certain biochemical constituents or coagulation variables have not been extensively documented. PATIENTS AND METHODS: During the month of Ramadan and two months after, we monitored the concentration of different plasma lipoproteins, lipoprotein (a) [Lp(a)], apoproteins A(1) and B, fibrinogen, factor VII activity and some selected hematological factors in 50 healthy subjects who were employees of institutes related to the Isfahan University of Medical Sciences and aged between 30 and 45 years. The effect of fasting in Ramadan on the relationship between biochemical and coagulation variables was also investigated. RESULTS: The values of apoprotein B, Lp(a) and low-density lipoprotein cholesterol (LDL-C)/high-density lipoprotein cholesterol (HDL-C) ratio were significantly decreased during Ramadan (P<0.05), while total cholesterol (Tot-C), triglycerides (TG), LDL-C, HDL-C and fasting blood glucose did not change during that month. Among coagulation and hematological factors, fibrinogen level and factor VII activity were significantly decreased during the month (P<0.05). Results also indicated a significant positive association between fibrinogen level and Lp(a), factor VII activity and Tot-C, LDL-C, TG and Apo B during Ramadan. CONCLUSION: Our findings contribute to a better understanding of previous reports, as the metabolic and coagulation changes that are considered as atherosclerosis risk factors are counterbalanced during Ramadan.

Elucidation of pKa values for Ca2+ binding sites in calmodulin by spectrofluorometry.

Calmodulin (CaM) was purified from bovine brain and identified on the basis of its phosphodiesterase activity. Its purity was further tested by electrophoretic migration in polyacrylamide gels in the presence of sodium dodecyl sulfate. Apo-CaM was prepared from holo-CaM using hydroxyapatite chromatography. The Ca2+ binding sites on CaM and the pKa of each of the functional groups bound to Ca2+ were identified from the dependence of Ca2+ interaction with the functional group as a function of pH. EGTA was found to diminish the peaks corresponding to the pKa values of the groups bound to Ca2+. The use of bromophenacyl bromide, a modifier for aspartate and glutamate residues in proteins, diminished the peaks at pH = 3.4 and 4.3. Diethyl pyrocarbonate, a modifier for histidine residues, reduced the peak at pH = 6.2, corresponding to the pKa of the imidazole group in histidine. Furthermore, the peak at pH = 11.6 was eliminated using the specific tyrosine modifier, N-acetylimidazole. Diethylpyrocarbonate also eliminated four small peaks at pH = 7.2, 7.8, 8.2 and 8.8. This effect could be attributed to the binding of threonine and serine residues. The crystallographic results for parvalbumin, which has a similar molecular structure, suggest identical Ca2+ binding sites.