Androgenetic Alopecia From A to Z: Vol.1 Basic Science, Diagnosis, Etiology, and Related Disorders

Foreword
Preface
Acknowledgments
Contents
Part I: The Hair Follicle Biology and Life
	1: Hair Through the Ages
		1.1	 Why Is Hair So Important?
		1.2	 Influences
		1.3	 Socio-cultural Impact of Hair Loss
		1.4	 Hair in Prehistoric Antiquity
		1.5	 Hairdressing in Greek and Roman Antiquity
		1.6	 Middle Ages
		1.7	 Renaissance
		1.8	 The Century of the Wig
		1.9	 From the Nineteenth to the Twenty-first Century
		1.10	 Hair Today
		1.11	 Synopsis
		References
	2: The Mission of Hair Follicles and Hair
		2.1	 Functions of Hair Follicles
			2.1.1	 Sensation
			2.1.2	 Thermoregulation and Insulation
			2.1.3	 Protection from Solar Radiation
			2.1.4	 Physical Protection
			2.1.5	 Communication
		2.2	 Why Humans Lost Their Coat?
		2.3	 Is There An Evolutionary Explanation for AGA?
			2.3.1	 Theories on the Evolutionary Roles of AGA
			2.3.2	 What About FPHL?
		2.4	 What Is the “Role” of AGA Today?
		2.5	 Synopsis
		References
	3: Embryogenesis of Pilosebaceous Unit
		3.1	 History of Follicular Embryology
		3.2	 Hair Follicle Morphogenesis
		3.3	 Stages of the Embryological Development of Human Hair Follicles
		3.4	 Molecular Mediation of Follicular Embryogenesis
		3.5	 Synopsis
		References
	4: Morphology and Histology of the Pilosebaceous Unit
		4.1	 Hair Follicle Morphology
			4.1.1	 Bulb
				4.1.1.1	 Dermal Papilla
				4.1.1.2	 Inner Root Sheath
				4.1.1.3	 Outer Root Sheath
				4.1.1.4	 Vitreous Membrane
				4.1.1.5	 Connective Tissue Sheath
			4.1.2	 Suprabulbar Region
			4.1.3	 Isthmus
			4.1.4	 Infundibulum
		4.2	 Arrector Pili Muscle (APM)
		4.3	 Sebaceous Gland
		4.4	 Vascularization of the Hair Follicle
		4.5	 Synopsis
		References
	5: The Life Cycle of the Hair Follicle
		5.1	 A Cycle Unlike Any Other!
		5.2	 Why Do Mammals Have Fur Coats?
		5.3	 The Hair Follicle Life Cycle in Mammals and Humans
		5.4	 The Rhythm of Life of the Hair Follicle
		5.5	 Stages in the Cycling of Hair Follicles
			5.5.1	 The Anagen Stage
			5.5.2	 The Catagen Stage
			5.5.3	 The Telogen Stage
			5.5.4	 The Exogen Stage
			5.5.5	 The Kenogen Stage
		5.6	 Duration of Cycle Stages
		5.7	 Mosaic Hair Art!
		5.8	 Synopsis
		References
	6: The Morphology and Structure of the Hair Shaft
		6.1	 Basic Hair Anatomy
			6.1.1	 The Cuticle
			6.1.2	 The Cortex
			6.1.3	 The Medulla
		6.2	 The Chemical Composition of Hair
			6.2.1	 Protein
			6.2.2	 Water
			6.2.3	 Lipids
			6.2.4	 Melanin
			6.2.5	 Trace Elements
		6.3	 Chemical Bonds in Hair
			6.3.1	 Hydrogen Bonds
			6.3.2	 Salt Bonds
			6.3.3	 Cystine or Disulfide Bonds
			6.3.4	 Carbohydrate Bonds
		6.4	 Physical Properties of Hair
			6.4.1	 Hair Caliber
			6.4.2	 Tensile Strength and Torsion Forces
			6.4.3	 Compability
		6.5	 Synopsis
		References
	7: Types of Hair Follicles in Humans
		7.1	 Types of Hair Follicles
			7.1.1	 Lanugo Hair Follicle
			7.1.2	 Vellus Hair Follicle
			7.1.3	 Intermediate Hair Follicle
			7.1.4	 Terminal Hair Follicles
		7.2	 Transformation of Hair Follicles
		7.3	 Synopsis
		References
	8: The Effects of Aging on the Hair Follicle
		8.1	 Senile Alopecia vs. AGA: How Are they Different?
			8.1.1	 Is AGA Related to SA?
		8.2	 Hair Weathering
		8.3	 Graying
			8.3.1	 It’s Just an Illusion!
			8.3.2	 Premature Hair Graying
		8.4	 The Pathophysiology of Hair Graying
			8.4.1	 The Effects of Depigmentation on the Hair Fiber
			8.4.2	 Is Graying Reversible?
			8.4.3	 Canities and AGA
		8.5	 Synopsis
		References
Part II: Diagnosis of Androgenetic Alopecia
	9: Hair Growth Assessment Techniques in AGA/FPHL
		9.1	 Historical Overview
		9.2	 Methods for the Assessment of Hair Disorders
			9.2.1	 Hair Pull Test & Hair Feathering Test
			9.2.2	 Wash Test
			9.2.3	 Hair Weighing
			9.2.4	 Global Photography
			9.2.5	 Unit Area Trichogram
			9.2.6	 Phototrichogram (PTG)
			9.2.7	 Automated Phototrichogram: TrichoScan®
			9.2.8	 Dermoscopy and Trichoscopy
			9.2.9	 Digital Dermoscopy/Trichoscopy
			9.2.10	 Scalp Biopsy
		9.3	 Author’s Notes
		9.4	 Synopsis
		References
	10: Diagnostic Steps in the Evaluation of AGA/FPHL
		10.1	 Patient Medical History
		10.2	 Laboratory Tests
		10.3	 Gynecological History
		10.4	 Clinical Evaluation
			10.4.1	 Scalp Examination
			10.4.2	 Hair Examination
			10.4.3	 Trichoscopy
			10.4.4	 Clinical Picture
				10.4.4.1	 AGA
				10.4.4.2	 FPHL
				10.4.4.3	 Examination of Facial and Body Hair
		10.5	 Synopsis
		References
Part III: Causes and Etiologic Parameters of AGA/FPHL
	11: Hormonal and Genetic Etiology of Male Androgenetic Alopecia
		11.1	 Definition
		11.2	 Phenotype and staging of AGA
		11.3	 Natural Course of AGA
		11.4	 Epidemiology of AGA
		11.5	 Interracial Differences in AGA Epidemiology
		11.6	 Pathophysiology of AGA
			11.6.1	 Follicular Miniaturization
		11.7	 Inheritance of AGA
			11.7.1	 Some Background
			11.7.2	 Genetic Associations and AGA
			11.7.3	 Latest Findings in Genome Studies
		11.8	 Hormones and AGA
			11.8.1	 General Mechanism of Hormonal Action
			11.8.2	 Mechanism of Action of Androgens
			11.8.3	 How Did Androgens Correlate with AGA?
			11.8.4	 Androgens and Hair Follicles in Animals
			11.8.5	 Androgens and Hair Follicles in Humans: AGA and Observational Studies
			11.8.6	 Which Androgen Actually Causes Hair Loss?
			11.8.7	 Enzymic System of 5α-Reductase (5α-R)
		11.9	 Effects of Androgens in Hair Growth in General
		11.10	 Why Some Men Develop AGA, and Others Do Not?
			11.10.1 Androgen Production
			11.10.2 Androgen Transfer
			11.10.3 Metabolism of Androgens in the Hair Follicles
			11.10.4 Cellular Response to Androgen Action
				11.10.4.1	 Genomic Mode of Action
			11.10.5 Nongenomic Mechanism of Action
		11.11	 How Exactly Do Androgens Act on the Hair Follicles?
		11.12	 Other Chemical Factors and AGA
		11.13	 Joining the Pieces
		11.14	 Recent Exciting Findings
			11.14.1 MicroRNAs
			11.14.2 Prolactin
			11.14.3 BDNF (Brain-Derived Nerve Factor)
			11.14.4 PCNAs
			11.14.5 Wnt/β-catenin Signaling Pathway
			11.14.6 IL-6
			11.14.7 Prostaglandins, PTGDS
		11.15	 Synopsis
		References
	12: Female Pattern Hair Loss
		12.1	 Some History on Female AGA Aka FPHL
		12.2	 Histological and Phenotypic Features
		12.3	 FPHL and Androgens
		12.4	 Is FPHL Androgen-Independent?
			12.4.1	 Laboratory Tests
		12.5	 Genetics and FPHL
		12.6	 FPHL Presentation and Classification
			12.6.1	 Hamilton Scale
			12.6.2	 Ludwig Scale
			12.6.3	 Olsen Scale
			12.6.4	 Savin Scale
			12.6.5	 Sinclair Scale
		12.7	 Some Unique Features in FPHL Phenotype
		12.8	 Age at the Onset of FPHL
		12.9	 Incidence and Prevalence of FPHL
		12.10	 The Natural Course of FPHL
		12.11	 FPHL and Menopause
		12.12	 Management of FPHL
		12.13	 Synopsis
		References
	13: AGA/FPHL in Children and Adolescents
		13.1	 Hair Loss in Children
		13.2	 AGA in Children
			13.2.1	 Pathophysiology
			13.2.2	 Prevalence
		13.3	 Clinical Presentation and Differential Diagnosis
			13.3.1	 History and Clinical Examination
			13.3.2	 Systemic Associations
			13.3.3	 Studies on Children
			13.3.4	 Treatment
		13.4	 AGA in Adolescents
			13.4.1	 Pathophysiology
			13.4.2	 Prevalence
			13.4.3	 Clinical Presentation and Differential Diagnosis
			13.4.4	 History and Clinical Examination
			13.4.5	 Systemic Associations
			13.4.6	 Treatment
				13.4.6.1	 Minoxidil
				13.4.6.2	 Finasteride
			13.4.7	 Other Anti-androgens
		13.5	 Synopsis
		References
	14: Hair Follicle Microinflammation in AGA/FPHL
		14.1	 Immune Privilege and the Hair Follicle
		14.2	 Microinflammation, Fibrosis, and AGA
			14.2.1	 Microinflammation and Microbial Involvement
			14.2.2	 Microinflammation, Cytokines, and Inflammatory Cells
		14.3	 Hair Follicle Microinflammation and Androgens
		14.4	 Inflammasomes, Caspase-1 και AGA
		14.5	 Inflammation and Cicatricial Alopecia
		14.6	 Synopsis
		References
	15: The Role of the Sebaceous Gland in AGA/FPHL
		15.1	 About the Sebaceous Gland
		15.2	 The Endocrinology of the Sebaceous Gland
			15.2.1	 Sebaceous Gland, Enzymes, and Hormones
			15.2.2	 Sebaceous Gland and Androgen Production
			15.2.3	 The Sebaceous Gland, Androgens, and AGA
			15.2.4	 The Sebaceous Gland, Microbial Flora and Hair Loss
		15.3	 Is There a Conclusion?
		15.4	 Synopsis
		References
	16: The Role of Scalp Vascularization in AGA/FPHL
		16.1	 Theories of the Past
		16.2	 A Bit of Anatomy
		16.3	 Vascular Changes in AGA
			16.3.1	 Pathophysiologic Mechanisms
			16.3.2	 Scalp Changes in AGA
			16.3.3	 DHT and Vessels
		16.4	 Synopsis
		References
	17: The Role of Biochemical Stress in AGA/FPHL
		17.1	 Stress and the Skin
		17.2	 Is Stress Linked to Hair Loss?
			17.2.1	 Experimental Models and Stress
			17.2.2	 Stress as a Cause of Hair Loss in Animals
			17.2.3	 Stress as a Cause of Hair Loss in Humans
			17.2.4	 Stress and AGA. Is there a Link?
			17.2.5	 Stress Caused by Hair Loss Per Se
			17.2.6	 Putting the Pieces Together
		17.3	 Synopsis
		References
	18: The Role of Solar Radiation in AGA/FPHL
		18.1	 UVR and the Hair Follicle
		18.2	 UVR and AGA/FPHL
		18.3	 UVR-Induced Microinflammation
		18.4	 UVR-Induced Hair Damage
		18.5	 Photoprotection of the Scalp
		18.6	 Synopsis
		References
	19: Other Hormones Related to AGA/FPHL
		19.1	 Thyroid Hormones
		19.2	 Actions of Thyroid Hormones on the Hair Follicle
			19.2.1	 Systemic Effects
			19.2.2	 Local Administration of Thyroid Hormones
			19.2.3	 Studies in Human Hair Follicles
			19.2.4	 Clinical Studies
		19.3	 Parathyroid Hormone and Parathyroid Hormone-Related Protein
		19.4	 Vitamin D
		19.5	 Synopsis
		References
	20: The Psychological Effects of AGA/FPHL
		20.1	 Understanding and Empathy
		20.2	 Is It Just Vanity?
		20.3	 Physical Attractiveness Phenomena
		20.4	 AGA and Stereotypes
		20.5	 How Do Others View Balding Men?
		20.6	 How Do Men with AGA Feel About Themselves?
		20.7	 Do All Men with AGA Feel the Same?
			20.7.1	 Coping Mechanisms
		20.8	 The Psychological Effect of FPHL on Women
		20.9	 Patient Self-Evaluation of Hair Loss
		20.10	 How the Treatment of AGA Affects Patient Psychology
		20.11	 Should We Treat More Than Hair Loss?
		20.12	 Synopsis
		References
Part IV: AGA/FPHL and Comorbidities
	21: Cardiovascular Disease, Insulin Resistance, Metabolic Syndrome, and AGA/FPHL
		21.1	 Cardiovascular Disease and AGA
		21.2	 Is AGA (or a Specific Pattern of AGA) a Sign of CVD?
		21.3	 Studies on the Correlation Between CVD and AGA
		21.4	 Studies on the Link Between CVD and FPHL
		21.5	 Metabolic Syndrome and AGA
		21.6	 Studies on the Link Between Insulin Resistance, Metabolic Syndrome, and AGA
		21.7	 Arterial Hypertension and AGA
		21.8	 Can There Be a Unified Theory?
		21.9	 Synopsis
		References
	22: Prostate Disorders and AGA
		22.1	 Prostate Cancer
			22.1.1	 Androgens and Prostate Cancer
			22.1.2	 Similarities Between PCa and AGA
			22.1.3	 Why Are We Interested in the Relationship Between AGA with PCa?
			22.1.4	 Studies on the Correlation of PCa with AGA
			22.1.5	 Genome-Wide Association Studies (GWAS), AGA and PCa
		22.2	 Benign Prostatic Hyperplasia and AGA
		22.3	 AGA and Other Androgen-Related Disorders
		22.4	 Synopsis
		References
Index