The current burden of non-communicable diseases (NCDs) and their risk factors such as tobacco use and physical inactivity remain largely unknown in Sierra Leone. Thus, this study was conducted to document the prevalence of tobacco use and physical activity among the adult Sierra Leonean population with a specific objective of determining the sex and age prevalence. A cross sectional population based survey utilising the multi-stage cluster sampling strategy was used. A total of 5,483 individuals aged 25-64 years of both sexes were recruited into the survey. The World Health Organisation (WHO) STEPwise approach to surveillance instrument was adapted and questionnaire was administered to one individual in selected household. The data was analysed and graphed using Epi-Info software version 3.4.3 and graph pad prism version 5.1 respectively. The analyses showed that 34% of the respondents use tobacco products with 26% engaged in smoking tobacco products and 8% were smokeless tobacco users at the time of this study. The average age of commencing tobacco smoking was 21 years; with 92% and 96% of the male and female daily smokers smoking at least six manufactured tobacco respectively. Seventy four percent (74%) and 69% of the non-smoking respondents were exposed to environmental tobacco smoke (ETS) at home and workplace respectively. The study further revealed that 15%, 23% and 87% of the total respondents reported no work-, transport-or recreational-related physical activity respectively; and were therefore classified as physically inactive. The lowest level of physical activity was reported in the recreation domain. Even those who reported moderate physical activity at work or from travel, their median metabolic equivalent (MET) was not sufficient to achieve a level of physical activity that is beneficial to their health. In conclusion, a significant proportion of the population is exposed either directly or indirectly to tobacco smoke, and a large proportion of the adult population is physically inactivity. Thus, NCD prevention policy addressing lifestyle changes such as no smoking should not be limited to work places but should be population based.

Renal toxicity produced by paraquat involves the generation of reactive oxygen species (ROS) which can overwhelm antioxidant defences, leading to oxidant injury. However, there are conflicting reports regarding the activity and/or expression of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) during oxidative stress injury. This study investigated the activity and expression of these enzymes in a renal epithelial cell line following exposure to paraquat. Confluent NRK-52E cells were incubated with increasing concentrations of paraquat (1-100mM) for up to 24 hours. Renal cell death was determined by measurement of lactate dehydrogenase release. Oxidant damage was determined via measurement of malondialdehyde formation and DNA strand breaks. The effects of paraquat on DNA and de novo protein synthesis were determined using radio-labelled thymidine and leucine respectively. ROS generation (superoxide anion and hydroxyl radical formation) was measured using nitrobluetetrazolium and deoxyribose assays. Antioxidant enzyme activities and expression were measured using established biochemical assays and Western blot analysis. Exposure of confluent NRK-52E cells to paraquat resulted in significant cell death involving increased lipid peroxidation, DNA damage and inhibition of DNA and de novo protein synthesis. Renal cell injury and death were secondary to increased ROS generation. Incubation with paraquat reduced SOD and CAT activities; in contrast, GSH-Px activity increased significantly. Although SOD expression was significantly reduced, catalase expression was unaffected. These results indicate that paraquat mediates renal toxicity via oxidative stress involving both an increase in ROS generation and reductions in SOD and CAT activities with a concomitant reduction in SOD expression.