Free Radicals and Antioxidants | Biochemistry, Oxidative Stress & Diseases Explained | MBBS/NEETPG

In this video, we break down the complex biochemistry of free radicals and antioxidants into simple concepts. You'll learn what free radicals really are (the "sparks" that cause cellular fires), how they are formed in the mitochondria, and the chain reactions that lead to oxidative stress.

We also explore the body's powerful antioxidant defense systems—both enzymatic (SOD, Catalase, Glutathione) and non-enzymatic (Vitamin C, E)-and how they neutralize these threats. Finally, we discuss the clinical significance of oxidative stress in aging, diabetes, heart disease, and cancer.

Whether you are a medical student, biochemistry student, or just curious about how your body fights aging and disease at a molecular level, this video is for you!

🔍 WHAT YOU WILL LEARN:
✅ What are Free Radicals? (Unpaired electrons & reactivity)
✅ Sources of ROS: Mitochondrial ETC, NADPH oxidase (respiratory burst), and external pollutants
✅ The 3 Stages: Formation, Chain Reaction, and Molecular Damage (Lipid Peroxidation, DNA damage)
✅ Enzymatic Antioxidants: Superoxide Dismutase (SOD), Catalase, Glutathione Peroxidase
✅ Non-Enzymatic Antioxidants: Vitamin C, Vitamin E, Glutathione, Uric Acid
✅ Regulation: The Nrf2-KEAP1 Pathway (The master switch!)
✅ Clinical Links: G6PD Deficiency, Diabetes, Alzheimer's, Cancer & Aging

🕐 TIMESTAMPS / CHAPTERS:
00:00 - Introduction: The "Spark" and the Fire
01:21 - What are Free Radicals? (Definition)
01:48 - How are Free Radicals Formed? (Mitochondria & Enzymes)
02:50 - Enzymatic Sources (NOX, Xanthine Oxidase) & Respiratory Burst
03:54 - External Sources: Pollution, UV Rays, Smoking
04:45 - The Chain Reaction: Superoxide to Hydroxyl Radical
05:25 - The Fenton Reaction (Iron & H2O2)
06:12 - Molecular Damage: Lipid Peroxidation (PUFAs & MDA)
07:05 - Protein Oxidation & DNA Damage
07:56 - Enzymatic Antioxidants (SOD, Catalase, Glutathione System)
09:47 - G6PD Deficiency & Hemolytic Anemia Connection
11:06 - Non-Enzymatic Antioxidants (Vitamin C, Glutathione, Uric Acid)
12:12 - Lipid-Soluble Antioxidants (Vitamin E, CoQ10)
13:05 - The Antioxidant Cycle (How they help each other)
13:58 - Regulation: Nrf2-KEAP1 Pathway Explained
16:03 - Clinical Significance: G6PD, Diabetes, & Heart Disease
17:10 - Oxidative Stress in Neurodegeneration (Alzheimer's) & Cancer
18:05 - Summary & Key Takeaways

🎯 THIS VIDEO IS USEFUL FOR:
• MBBS / MD / Medical Students
• Biochemistry & Nursing Students
• USMLE / NEET PG Aspirants
• Anyone interested in the science of Aging & Longevity

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📚 RECOMMENDED STUDY TOPICS:
• Electron Transport Chain (ETC)
• Pentose Phosphate Pathway (HMP Shunt)
• Inflammation & Immunology

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