Paraoxonase (PON1) activity in north west Indian Punjabis with coronary artery disease & type 2 diabetes mellitus.

BACKGROUND & OBJECTIVE: Paraoxonase (PON1), an arylesterase is associated with high density lipoprotein cholesterol (HDL-C). PON1 prevents low density lipo-protein cholesterol (LDL-C) from peroxidation and can also hydrolyze lipid peroxides, thereby providing protection against atherosclerosis and coronary artery disease (CAD). The incidence of CAD is known to be high in north western Indian Punjabis. Though many factors may play a role in its pathogenesis, low PON1 activity could be an independent risk factor. We carried out this study to determine PON1 activity in north-west Indian Punjabi patients with CAD with and without type 2 diabetes mellitus and compared with healthy individuals. METHODS: A total of 120 patients with angiographically proven CAD (57 with and 63 without type II diabetes mellitus) and 19 healthy controls were studied for plasma PON1 activity and lipid variables. Comparison was undertaken between CAD patients and healthy controls and between CAD patients with and without type II DM. RESULTS: Significantly lower plasma PON1 activity (P<0.05) along with lower HDL-C (P<0.001) and higher LDL-C (P<0.05) levels were observed in CAD patients as compared to healthy controls. On univariate analysis of variance after adjusting for age and sex, no significant difference could be observed between PON1 activity and age and sex. On discriminant analysis, no clear cut-off could be observed in PON1 activity between patients CAD and controls. Similarly between CAD with and without patients type II diabetes mellitus, there was no significant difference in PON1 activity and lipids. INTERPRETATION & CONCLUSION: The low plasma PON1 activity irrespective of being diabetic may be an independent risk factor for CAD in north-western Indian Punjabi population. Similar studies involving larger samples in different ethnic groups in India need to be done to find out the role of PON1 activity in CAD.

Paraoxonase (PON1) polymorphism & its relation with lipids in north west Indian Punjabis.

We investigated 190 healthy, unrelated and randomly selected, north-west Indian Punjabis (M:102; F:88) for paraoxonase (PON1) polymorphism by dual substrate method and also determined lipid variables i.e., total cholesterol (TC), high density lipoprotein cholesterol (HDL), low density lipoprotein cholesterol (LDL) and triglycerides (TG) in them to determine any relationship between PON1 activity, PON1 phenotypes and lipids. The basal plasma paraoxonase (PON) activity, and PON activity in presence of 1 Mol NaCl (salt activated paraoxonase i.e., SAP) were estimated by using paraoxon as substrate whereas the, phenyl acetate esterase (A) activity was estimated by using phenylacetate as substrate. Based on the ratio of SAP/A activity, three distinct phenotypes of PON1 could be determined with gene frequencies of PON*A (low activity) and PON*B (high activity) allele being 0.847 and 0.153 respectively. In the whole population on partial correlation after normalising the variables and after adjusting the lipids for age and body mass index (BMI), a significant negative correlation was observed between SAP/A ratio and TC (r = -0.290; P < 0.01) and LDL (r = -0.154; P < 0.05). However, on analysis of covariance (ANCOVA) after normalizing the lipid variables and adjusting these for age and body mass index (BMI), no significant difference could be observed in lipid profile of these three phenotypes. The lack of a significant relationship between lipids and PON1 phenotypes, suggests that PON phenotype does not significantly influence the lipid profile in north-west Indian Punjabis. However, a significant negative correlation between the PON activity and TC and LDL suggests that low PON activity could be a risk factor for atherosclerosis in these subjects.

Public awareness, understanding & attitudes toward epilepsy.

The public awareness, understanding and attitudes towards epilepsy were evaluated in a north Indian population in 1992 by personal interview method. The study revealed that 92 per cent of the respondents had read or heard about epilepsy. More than 55 per cent knew someone and had seen a case of seizure. Eighty five per cent of the respondents were not aware of the cause of epilepsy or had wrong beliefs. Eighteen and 15 per cent thought epilepsy to be a hereditary disorder and a form of insanity respectively. About 40 per cent of the respondents felt that children with epilepsy should not be sent to school and also objected to their children's contact with epileptics at school or at play. Two-thirds of the respondents objected to their children marrying a person who had ever had epilepsy. Twenty per cent were ignorant about the manifestation of epilepsy and an equal number were unable to recommend any therapy in case their relatives or friends had epilepsy. Fifty seven per cent did not know what kind of first aid should be given during the epileptic attack. Although the awareness of epilepsy among Indian people was comparable to that of individuals in Western countries, the attitudes of the Indians were much more negative. Better educated people belonging to higher occupational groups were less prejudiced against social contact and schooling of their children with epileptic children compared to low educational and occupational groups.