p16INK4a and γ-H2AX as Biomarkers of Senescence in Skin Tissue: A Cadaveric Cross-sectional Study at a Tertiary Care Centre in Punjab, India
Published: October 1, 2023 | DOI: https://doi.org/10.7860/JCDR/2023/64549.18613
Richa Gupta, Anjali Aggarwal, Tulika Gupta, Chiman Kumari
1. Assistant Professor, Department of Anatomy, PGIMER, Chandigarh, India.
2. Professor and Head, Department of Anatomy, PGIMER, Chandigarh, India.
3. Associate Professor, Department of Anatomy, PGIMER, Chandigarh, India.
4. Associate Professor, Department of Anatomy, PGIMER, Chandigarh, India.
Correspondence
Dr. Anjali Aggarwal,
Professor and Head, Department of Anatomy, PGIMER, Chandigarh-160012, Punjab, India.
E-mail: anjli_doc@yahoo.com
Introduction: Baseline expression of p16INK4a characterises cellular senescence. Similarly, the measurement of γ-Gamma-H2AX (γ-H2AX) foci levels in cells provides a reliable method for quantification of Deoxyribonucleic Acid (DNA) damage.
Aim: To explore the role of p16INK4a and γ-H2AX as biomarkers of senescence in skin tissue.
Materials and Methods: This was a cross-sectional study conducted in the Department of Anatomy, PGIMER, Chandigarh, Punjab, India from June 2022 to January 2023. Skin tissue was obtained from 30 cadavers, aged 20-90 years, from the anterior abdominal wall. The time duration of sample collection after death varied from six hours to 12 hours. Samples were divided into two groups: Group-I <30 years and Group-II >70 years, with n=15 in each group. The relative change in the expression pattern of p16INK4a and γH2AX markers, as well as the microstructure of the skin (thickness of epidermis and dermis, distribution of collagen I/II/III fibres, architecture of sebaceous glands), were statistically analysed using an unpaired t-test.
Results: Intense staining was observed with p16INK4a in Group-II, showing positivity in 60.75% of the cells, while Group-I depicted a weak staining pattern (15%). On immunostaining with γ-H2AX, only Group-II cells showed intense positivity (45%). Significant differences were observed in the epidermal and dermal thickness: Group-I (165.5267±37.73 μm; 2394.6±874.13 μm); Group-II (54.6±22.79 μm; 566.67±242.23 μm), and collagen Type-II/III fibres were found predominantly in aging skin tissue.
Conclusion: The present study provides comprehensive data regarding age-associated changes between p16INK4a, γ-H2AX, and skin microstructure, which result in decreased repair and regenerative capacity of skin tissue and various age-related skin diseases.
[
FULL TEXT ] | [ PDF]