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.     

Isfahan Healthy Heart Programme: a comprehensive integrated community-based programme for cardiovascular disease prevention and control. Design,methods and initial experience

The Isfahan Healthy Heart Programme (IHHP) is a five to six year comprehensive integrated community-based programme for cardiovascular diseases (CVD) prevention and control via reducing CVD risk factors and improvement of cardiovascular healthy behaviour in a target population. IHHP started late in 1999 and will be finished in 2005-2006. A primary survey was done to collect baseline data from interventional (Isfahan and Najaf-Abad) and reference (Arak) communities. In a two-stage sampling method, we randomly selected 5 to 10 percent of households from randomly selected clusters. Then individuals aged > or = 19 years were selected for the survey. This way, data from 12,600 individuals (6300 in interventional counties and 6300 in the reference county) was collected and stratified according to living area (urban vs. rural) and different age and sex groups. The samples underwent a 30-minute interview to complete validated questionnaires containing questions on demography, socioeconomic status, smoking behaviour, physical activity, nutritional habits and other behaviour regarding CVD. Blood pressure and body mass index (BMI) measurements were done and fasting blood samples were taken for two hours post load plasma glucose (2 hpp), serum (total, HDL and LDL) cholesterol and triglyceride levels. A twelve-lead electrocardiogram was recorded in all persons above 35 years of age. Community-wide surveillance of deaths, hospital discharges, myocardial infarction and stroke registry was carried out in the intervention and control areas. Four to five years of interventions based on different categories such as mass media, community partnerships, health system involvement and policy and legislation have started in the intervention area while Arak will be followed without intervention. Considering the results of the baseline surveys, (assessments needed, the objectives, existing resources and the possibility of national implementation) the interventions were planned. They were set based on specific target groups like school children, women, work-site, health personnel, high-risk persons, and community leaders were actively engaged as decision makers. A series of teams was arranged for planning and implementation of the intervention strategies. Monitoring will be done on small samples to assess the effect of different interventions in the intervention area. While four periodic surveys will be conducted on independent samples to assess health behaviours related to CVD risk factors in the intervention and reference areas, the original pre-intervention subjects aged more than 35 years will be followed in both areas to assess the individual effect of interventions and outcomes like sudden death, fatal and nonfatal MI and stroke. The whole baseline survey will be repeated on the original and an independent sample in both communities at the end of the study.     

Visceral obesity and incident cancer and cardiovascular disease: An integrative review of the epidemiological evidence

Evidence shows a strong relationship between obesity, cancer and cardiovascular disease (CVD) risk. However, there is not enough evidence of the role of visceral obesity on both CVD and cancer. Visceral obesity may be more pro‐oncogenic than total body fat. Therefore, it is important to know whether abdominal obesity can lead to both CVD and cancer. The present integrative review aimed at evaluating epidemiological evidence on the potential connection of visceral obesity in the occurrence of cancer and CVD. The following databases were searched: SCOPUS, PubMed, Science Direct, Lilacs, SciELO, Google Scholar, Web of Science, Scopus and ProQuest. The presence of visceral obesity can increase the risk of some specific cancer types, but there is controversial evidence about CVD risk based on sex‐specific and ageing analyses. There is enough evidence that visceral obesity increases the risk of colorectal, pancreatic and gastro‐oesophageal cancer. However, for some types of cancer such as breast, endometrial and renal, visceral obesity is a risk only in post‐menopausal women. Regarding prostate cancer, the evidence is controversial. Despite the risk of visceral obesity being consistently associated with CVD in adults, this association disappears in sex‐specific and older adults analyses. Moreover, in older adults, the results are controversial due to the use of different measures such as waist circumference and visceral adipose tissue. However, the evidence showing visceral obesity as a risk factor to CVD remains controversial. Sex differences, ageing and body mass index (BMI) category can potentially modify this association. Therefore, further epidemiological studies with analyses stratified by sex and samples including older adults aged 65 and older are needed.     

Vitamin E can reduce blood pressure in mild hypertensives

This triple-blind placebo-controlled clinical trial was performed to determine the effects of the anti-oxidant vitamin E on blood pressure and heart rate in patients with mild hypertension. A total of 70 new mild hypertensive subjects (systolic blood pressure, SBP: 140-160 mmHg; diastolic blood pressure, DBP: 90-100 mmHg) without secondary hypertension were selected from among people referred to the Hypertension Unit of Isfahan Cardiovascular Research Center and divided randomly into two groups of drug (DG) and placebo (PG). All subjects were aged from 20 to 60 years old, without any other cardiovascular risk factors. The drug group received vitamin E tablets (200 IU/day) and the placebo group received placebo only for 27 weeks. At the beginning and the end of the study, the blood vitamin E level was measured fluorimetrically in all subjects according to the Hansen and Warwick method [14, 15]. Blood pressure and heart rate were measured at the beginning, during, and at the end of the study. Blood pressure was measured by a physician using one random zero mercury sphygmomanometer. Personal information and dietary habits of subjects were collected by separate questionnaire. At the end of the study, it was found that the vitamin E supplement had caused a remarkable decrease in SBP (-24% in DG versus -1.6% in PG) and a less remarkable decrease in DBP (-12.5% in DG versus -6.2% in PG) (p < 0.05). The change in heart rate was -4.3% in DG, and -14.0% in PG (p < 0.05). It is concluded that a vitamin E supplement of 200 IU/day can be effective in mild hypertensive patients in the long term, probably due to nitric oxide, and improve their blood pressure status. Therefore, vitamin E supplement could be recommended to such patients.     

Tobacco use among Iranian men, women and adolescents

The aim of this study was to evaluate the self-reported and serum cotinine based prevalence rates of smoking among Iranian men, women and adolescents. The study was carried out on 2626 men and women aged 19 years and above and 836 high school students aged 14-18 years, randomly selected from different clusters and schools in Isfahan. The WHO smoking standard questionnaire was completed for all samples and serum cotinine level was measured using high-performance liquid chromatography in 10% and 20% of the original adult and adolescent samples, respectively. The prevalence of self-reported smoking among Iranian men and women aged 19 years and above was 18.7% and 1.3%, respectively, compared to 21.2% and 6.7% based on serum cotinine level. Nearly 10.6% and 14.6% of claimed nonsmoker girls and boys were classified as current smokers by serum cotinine level. More than 80% of male smokers started the habit before the age of 20 years and the effect of smoker friends was the most important factor for smoking initiation among smokers. Using self-reported prevalence data for smoking among women or adolescents in special populations like Iranians can give invalid measurements, therefore, data based on biochemical tests are suggested.     

Antioxidant activity of three extracts of Morus nigra

The antioxidant effect of three different extracts of Morus nigra fruit (fruit juice, hydroalcoholic and polyphenolic) on haemoglobin glycosylation, peroxidative damage to human erythrocytes, liver hepatooytes of rats and human low-density lipoprotein (LDL) were studied. The results show that all three extracts inhibited haemoglobin glycosylation induced by glucose to differing degrees. The haemolysis of human erythrocytes induced by hydrogen peroxide was also inhibited. The production of malondialdehyde (MDA) during peroxidative damage to plasma membranes of isolated rat hepatocytes induced by tert-butyl hydroperoxide (tBH) was also inhibited. Inhibition of lipid peroxidation of LDL induced by copper (II) ion was achieved during the study.The results suggest that Morus nigra fruit has a protective action against peroxidative damage to biomembranes and biomolecules.     

Sex differences in the impact of a community-based program for non-communicable disease prevention: The Isfahan Healthy Heart Program (IHHP)

Aims  To study the feasibility and impact of a comprehensive, integrated, community-based program directed towards reducing modifiable risk factors for cardiovascular disease. In this study, we reported the differences in the impacts of IHHP on physical activity, smoking and nutritional behaviors of a study population based on sex. Subjects and methods  Using multi-stage cluster sampling on people aged ≥19 years of both intervention and reference areas, 12,514 individuals in 2001, 5,891 in 2002, 4,793 in 2003 and 6,097 in 2004 as well as a sample of 3,011 participants from the intervention area in 2005 were enrolled. Women made up 50.8 percent of participants, with similar proportions from 2001 to 2005 and comparable distribution between intervention and reference areas. Eight distinct component interventional projects were designed separately for both sexes to improve modifiable risk factors in the intervention area. The WHO STEPwise risk factor surveillance questionnaires were used to conduct the annual cross-sectional surveys for behavioral changes. Estimates of intervention effect ratio were conducted based on annual changes in the behavioral modifiable risk factors for both men and women. Results  Intervention activities positively affected the total and leisure-time physical activities in men, but not women. Dietary choice of both sexes showed modest degrees of improvement. Smoking status of men improved in the study period (except 2004), while the effect on women was not significant. Conclusions  Further interventions to improve physical activity in women should be regarded as a health priority in Iran. Sex differences should be considered in implementing any health promotion activity. Grant no. HQ/03/873531, WHO Department of Chronic Disease and Health Promotion     

Why might South Asians be so susceptible to central obesity and its atherogenic consequences? The adipose tissue overflow hypothesis

The rates of coronary disease have accelerated dramatically amongst South Asians, driven to an important extent by the atherogenic dyslipidemia and type 2 diabetes that have become so common amongst them. These precursors of vascular disease appear at lower absolute amounts of adipose tissue in South Asians than in whites. In this paper, we set out a new hypothesis--the adipose tissue overflow hypothesis--to account for these findings. The adipose tissue mass within our bodies can be divided into three different compartments: superficial subcutaneous adipose tissue, deep subcutaneous adipose tissue and visceral adipose tissue. The superficial subcutaneous adipose tissue compartment is the primary compartment, is present throughout the body, and constitutes the vast majority of the adipose tissue in the lower limb. With energy excess, the secondary adipose tissue compartments--the deep subcutaneous (mainly upper body) and the visceral adipose tissue compartments--become more prominent. Superficial subcutaneous adipose tissue is relatively inert metabolically, whereas the other two compartments are characterized by higher transmembrane fatty acid flux rates and thus are more closely linked to dyslipidemia and dysglycemia. We hypothesize that the superficial subcutaneous adipose tissue compartment is larger in whites than in South Asians. If so, as obesity develops, South Asians exhaust the storage capacity of their superficial subcutaneous adipose tissue compartment before whites do and that is why they develop the metabolic complications of upper body obesity at lower absolute masses of adipose tissue than white people.