Evaluation of Oxidative Stress Biomarkers in Smokers and Non-Smokers

CHAPTER ONE

1.0 Background of the Study

Human health depends on the balance between oxidants and antioxidants in the body. When this balance shifts, oxidative stress occurs. Oxidative stress develops when reactive oxygen species (ROS) accumulate faster than the body can neutralize them (Halliwell & Gutteridge, 2015).

Cigarette smoking is one of the strongest external sources of oxidative stress. It introduces thousands of harmful compounds, including free radicals, tar, and heavy metals, directly into the bloodstream. These chemicals attack lipids, proteins, and DNA, thereby increasing oxidative damage (Pryor & Stone, 1993). As a result, smoking contributes to diseases such as cancer, atherosclerosis, and lung disorders.

The body fights oxidative stress through antioxidant enzymes such as superoxide dismutase (SOD) and catalase. These enzymes convert harmful radicals into less toxic compounds. However, when free radicals overwhelm these enzymes, damage increases rapidly (Valko et al., 2007).

Malondialdehyde (MDA), a product of lipid peroxidation, serves as an indicator of oxidative damage. Higher MDA levels suggest more cell membrane damage, while lower antioxidant enzyme activities show weaker defense systems. Therefore, comparing these biomarkers in smokers and non-smokers provides insight into the biochemical impact of tobacco use.

This study evaluates oxidative stress biomarkers to show how smoking disrupts the body’s natural antioxidant defenses.

1.1 Statement of the Problem

Cigarette smoking continues to harm millions of people worldwide. Although many studies warn against it, several individuals still underestimate its biochemical effects. Smoking introduces reactive compounds that accelerate oxidative damage. Unfortunately, the extent of this damage remains unclear to most people.

Therefore, it is necessary to measure specific oxidative stress biomarkers in smokers and compare them with those in non-smokers. This comparison will reveal the level of oxidative imbalance and support public health education.

1.2 Aim and Objectives of the Study

Aim:
To evaluate oxidative stress biomarkers in smokers and non-smokers.

Objectives:

1. To collect blood samples from smokers and non-smokers.

2. To measure oxidative stress biomarkers such as malondialdehyde (MDA), superoxide dismutase (SOD), and catalase.

3. To compare biomarker levels between smokers and non-smokers.

4. To assess the relationship between smoking intensity and oxidative damage.

5. To demonstrate how smoking increases oxidative stress.

1.3 Significance of the Study

This study is important because it shows the biochemical evidence of smoking-induced oxidative stress. The findings will help raise awareness about the hidden cellular damage caused by smoking. Moreover, they may assist healthcare professionals in developing antioxidant-based therapies for smokers.

In addition, the research will contribute to scientific knowledge on the relationship between lifestyle habits and oxidative stress. It will also encourage healthier choices among individuals exposed to cigarette smoke.

1.4 Scope of the Study

This study involves adult male and female participants aged 18 years and above. The participants will be grouped into smokers and non-smokers. Blood samples will be analyzed for MDA, SOD, and catalase activities using standard biochemical methods. However, the study will not account for diet, alcohol intake, or environmental pollutants that might affect oxidative balance.

1.5 Definition of Terms

Oxidative Stress: A harmful condition resulting from an imbalance between oxidants and antioxidants.
Free Radicals: Unstable molecules that can damage body cells and tissues.
Biomarker: A biological indicator used to measure a physiological or pathological process.
Malondialdehyde (MDA): A chemical product formed when free radicals attack lipids in cell membranes.
Superoxide Dismutase (SOD): An enzyme that protects cells by converting superoxide radicals into oxygen and hydrogen peroxide.
Catalase: An enzyme that breaks down hydrogen peroxide into water and oxygen, reducing oxidative stress.
Cigarette Smoke: A mixture of gases and chemicals from burning tobacco that contains toxic free radicals.