Unit 2 cosmetics and cosmaceuticals (Cosmetics - Biological aspects)

SKIN :-
Comprising three layers, the epidermis, dermis, and hypodermis, the skin is the biggest organ in the body. The dermis is home to hair follicles, each of which is attached to the arrector pili muscle.

Structure of skin:-
The outermost layer, the epidermis, contributes to skin tone and acts as a waterproof barrier.
Dermis: The middle layer that includes sweat glands, hair follicles, lymphatic and blood arteries, and connective tissue.
The innermost layer, the hypodermis, is composed of connective tissue and fat.

Hair composition :-
The hair follicle :- A tube-shaped sheath that envelops and nourishes the hair's subcutaneous portion
The arrector pili muscle :- Each hair follicle and the skin are attached to a little muscle that makes the hair stand up.

1. COSMETICS :- BIOLOGICAL ASPECTS Submitted to :- Submitted by :- Dr. (Prof.) Neelam Sharma Riya MMCP , Mullana Roll no. – 1424710 ( M.Pharmaceutics )

2. CONTENTS Structure of skin problems related to skin Dry skin Acne Pigmentation Prickly heat Wrinkles Body odour Structure of hair hair growth cycle

3. skin The skin is the body's largest and primary protective organ, covering its entire external surface and serving as a first-order physical barrier against the environment .

4. STRUCTURE OF SKIN

5. STRUCTURE OF SKIN

6. EPIDERMIS The epidermis is a thin layer of skin. The epidermis is composed of keratinized stratified squamous epithelium which contain four major types of cells :- ▪ Keratinocytes ▪ Melanocytes ▪ Langerhans cells ▪ Merkel cells This skin is further divided into five, separate layers. In order from most superficial to deepest, they are :- Stratum Corneum Stratum Lucidum Stratum Granulosum Stratum Spinosum Stratum Basale

7. Stratum Corneum :- This layer is composed of the many dead skin cells that shed into the environment . It also helps to repel water. Stratum Lucidum :- This layer is found only on the palms of the hands, fingertips, and the soles of the feet. Stratum Granulosum :- This is the layer where part of keratin production occurs. Keratin is a protein that is the main component of skin. Stratum Spinosum :- This layer gives the skin strength as well as flexibility. Stratum Basale :- It contains melanocytes, the cells that are largely responsible for determining the color of our skin and protecting our skin from the harmful effects of UV radiation.

8. DERMIS Underneath the epidermis lies the dermis. It contains :- Blood vessels that nourish the skin with oxygen and nutrients. The blood vessels also allow immune system cells to come to the skin to fight an infection. These vessels also help carry away waste products. Nerves that help us relay signals coming from the skin. These signals include touch, temperature, pressure, pain, and itching. Various glands Hair follicles Collagen , a protein that is responsible for giving skin strength and a bit of elasticity.

9. HYPODERMIS The deepest layer of the skin is called the subcutaneous layer, the subcutis, or the hypodermis. Like the dermis, the layer contains blood vessels and nerves for much the same reasons. Importantly, the subcutis contains a layer of fat. This layer of fat works alongside the blood vessels to maintain an appropriate body temperature . The layer of fat here acts as a cushion against physical trauma to internal organs, muscles, and bones. Additionally, the body will turn to this fat in times of starvation to provide power to its various processes, especially brain function.

10. FUNCTIONS Protection: The skin protects the body from various factors, including bacteria, chemicals, and temperature. It also protects against mechanical, thermal, and physical injury. Temperature regulation: The skin helps maintain body temperature within a specific range. When the body is too cold, the skin constricts blood vessels to conserve heat. When the body is too warm, the skin releases sweat to cool the body. Sensation: The skin is a sense organ that allows us to feel sensations like pain, pressure, temperature etc. UV radiation reduction: The skin contains melanin, a pigment that protects against ultraviolet light. Moisture prevention: The skin prevents the body from losing moisture. Wound healing: The skin plays an important role in wound healing.

11. PROBLEMS RELATED TO SKIN Dry skin Acne Pigmentation Wrinkles Prickly heat Body Odour

12. Dry skin Dry skin is skin that doesn't have enough moisture in it to keep it feeling soft. The medical term for dry skin is xeroderma. Xerosis is severely dry skin. Dry skin feels like rough patches of your skin that can flake or look scaly. It is characterized by red itchy skin that tends to crack and peel due to loss of moisture. It commonly affects the arms, legs, and feet .

13. CAUSES :- - Winter and autumn. - Hypothyroidism. - Chronic kidney disease. - Malnutrition and weight loss. - Skin conditions (such as: eczema and psoriasis). - Some medicines (e.g. diuretics and others). - Direct heat. - Frequent use of hot water. - Excessive bathing. - Using soaps and detergents - Ageing

14. Treatment / Prevention :- - Limited exposure to hot water while bathing. - Stay hydrated and apply moisturizing creams and ointments. - Limit your use of scented soaps and creams. - Apply moisturizing oils directly after bathing. - Avoid rubbing or scratching the skin - Wear gloves, hats, and scarves if the weather is cold. - Wear rubber gloves when using harsh cleansers. - Wear clothes made from natural cotton or silk to allow the skin to breathe. - Wash clothes with unscented detergents to avoid irritating the skin. - Drink plenty of fluids to stay hydrated .

15. acne Acne, also known as acne vulgaris It is an inflammatory skin condition that occurs when oil and dead skin cells block the pore opening , causing sebum (oil) to build up inside the pore. It is characterized by blackheads or whiteheads, pimples, oily skin and possible scarring. It primarily affects areas of the skin with a relatively high number of oil glands.

16. Causes :- Hormonal changes :- during puberty, pregnancy, menstrual cycles etc. the changes can cause the sebaceous glands to produce more oil, which can lead to clogged pores. Medications :- medications, such as those containing hormones, corticosteroids, lithium, iodides, or bromides, can cause or worsen acne. Family history :- Acne tends to run in families. Diet :- Some people may experience acne if they eat a lot of refined sugars or dairy products. Environment :- The environment you live in, such as humidity, temperature, and pollution, can contribute to acne. Skincare :- Using nails to pop pimples can cause inflammation.

17. Treatment/ Prevention :- Topical medications :- These come in many forms, including gels, lotions, creams, soaps, and pads. Common topical medications include benzoyl peroxide, retinoids, and sulfur. Oral medications :- These include antibiotics, isotretinoin, and spironolactone. Antibiotics are usually used for moderate to severe acne, while isotretinoin is a vitamin-A medication used to treat severe nodular acne. Hormonal therapies :- These can be effective for women with acne, but the progestogen-only pill or contraceptive implant can sometimes make acne worse. Self-care techniques :- These include washing your face twice a day with a mild soap or cleanser and lukewarm water, avoiding touching or picking acne-prone areas, and protecting your skin from the sun. Tea tree oil :- This essential oil may reduce acne and can be used as a spot treatment. However, it's very potent, so always dilute it before applying it to your skin. Lasers and light therapy Over-the-counter products :- Look for products that contain benzoyl peroxide, salicylic acid, glycolic acid, or alpha hydroxy acids. These can help reduce oil, break down blackheads and whiteheads, and promote peeling.

18. ACNE LIFE CYCLE Stage 1: Clogged Pores:- Cells lining pores shed and mix with excess sebum produced by sebaceous glands, forming a plug, which leads to clogged pores. Stage 2: Bacteria :- Accumulated sebum and dead cells attract propioni bacterium naturally found in skin, which feeds on oil and multiplies rapidly inside pores. Stage 3: Inflammation :- This bacterial overgrowth triggers the natural inflammatory response causing swelling and redness. This can ultimately lead to discoloration and scarring.

19. pigmentation Skin color is due to a pigment, called melanin. Melanin is produced by melanocytes , responsible for the coloration of skin, hair and eyes. Melanin is synthesized by melanocytes within melanosomes and transferred to keratinocytes. Pigmentation disorders are disturbances of human skin color, either loss or reduction, which may be related to :- ➢ loss of melanocytes or the ➢ inability of melanocytes to produce melanin or ➢ transport melanosomes correctly. Pigmentation is the coloring of an individual’s skin. The color of skin appears normal when a person is healthy. A person’s skin may change color and grow darker (hyperpigmentation) or lighter (hypopigmentation) because of illness and/ injury.

20. TYPES OF PIGMENTATION

21. HYPERPIGMENTATION :- Melasma : It is a common skin condition that causes brown or gray-brown patches or freckle-like spots on the face Lentigo : patch of skin that is darker than the surrounding skin as a result of an increased number of pigment cells. Latrogenic Hyperpigmentation : Due to excess production of melanin. Appearance of black spots Post acneic Hyperpigmentation : a chronic skin condition that occurs when skin darkens after an injury or inflammation. HYPOPIGMENTATION :- Vitiligo : white patches appear on the skin due to a loss of skin pigment.

22. PROCESS OF MELANIN PRODUCTION

23. Causes :- Sun damage Certain medications Skin injuries related to acne vulgaris Excess production of melanin Hormonal changes due to pregnancy Presence of endocrine disease like Addison’s disease Inflammation Excess exposure to sunlight.

24. Treatment :- Hydroquinone :- HQ affects not only the formation and degradation of melanosomes but it also affects the membranous structures of melanocytes and eventually causes necrosis of whole melanocytes. HQ concentration 2-5% applied once daily. Azelaic acid :- Azelaic acid is a naturally occurring non phenolic, saturated, 9 carbon dicarboxylic acid that competitively inhibit tyrosinase. Glycolic acid :- Glycolic acid is an α hydroxy acid that is usually combined with other agents at a concentration of 5-10% for its skin lightening property. Niacinamide :- The biologically active form of niacin(vit-B3) can reduce pigmentation by reversibly the transfer of melanosomes from the melanocytes to the keratinocytes.

25. wrinkles Wrinkles are the lines and creases that form in the skin. A wrinkles also known as rhytide, is a fold, ridge or a crease in the skin. Skin wrinkles typically appear as a result of ageing process such as habitual sleeping positions, loss of body mass, or as a result of prolonged immersion in a water. • It is specially noticeable around the eyes, mouth and neck some wrinkles can become deep crevices or a furrows.

26. Causes :- Aging :- With age the skin becomes less elastic and drier, and the fat and collagen in the skin decreases. This results in wrinkles and saggy skin. Sun exposure :- UV radiation from the sun breaks down the collagen and elastin fibers of skin, which causes it to lose strength and flexibility , early wrinkles. Smoking :- Smoking can speed up the aging process of your skin, which can contribute to wrinkles. Facial expressions :- Facial movements like smiling, squinting create grooves in the skin that can become permanent wrinkles. Pollution :- Pollutants in the air break down skin's collagen. Genetics :- The genes play a big role in how skin looks .

27. Prevention :- Moisturize: Dry skin can lead to wrinkles, so moisturize your skin daily. Moisturizers can also temporarily mask fine lines and wrinkles. Healthy diet: Eat plenty of fruits and vegetables, and consider eating salmon and other cold-water fish, which are high in protein and omega-3 fatty acids. Stay hydrated: Drink at least 2.7 liters of water per day. Protect the skin from the sun : Limit time in the sun, especially at midday, and Use a broad-spectrum sunscreen with an SPF of at least 30, and reapply every two hours. Wash face gently: Scrubbing your skin can irritate it and accelerate aging. Wash your face twice a day, and after sweating. Quit smoking: Smoking can negatively impact your skin tone and texture. Exercise moderately: Moderate exercise can improve circulation and boost your immune system, which may make your skin look more youthful. Drink less alcohol: Alcohol can dehydrate your skin and make you look older

28. PRICKLY HEAT It is also known as miliaria and heat rash . A heat rash occurs when sweat ducts become clogged and the sweat can’t get to the surface of the skin. It becomes trapped beneath the skin surface causing a mild inflammation of rash. The common symptoms of heat rash are red bumps on the skin, and an itchy or prickly feeling to the skin. Types of heat rashes 1.Clear 2.Red 3.white/yellow 4.deep.

29. Causes :- Sweating : Hot, humid weather, physical activity, illness with fever, and health conditions that cause extra sweating can all lead to prickly heat. Clothing : Tight or warm clothing, or clothing made of synthetic fabrics can trap sweat. Skin products : Heavy oils or petroleum jelly in skin products can clog pores and sweat glands. Other factors: Babies often get prickly heat because they can't control their temperature as well as adults and children. People who are overdressed in cool climates or who are hospitalized can also develop prickly heat.

30. Prevention : - Avoid hot, humid environments Avoid strenuous exercise when it's very warm Wear lightweight, loose-fitting clothes made of natural fibers like cotton, linen, or hemp Remove sweaty clothes after a long day Shower to wash off sweat and change into clean clothes Use air-conditioning or fans Take regular cool showers or baths

31. BODY ODOUR Body odor is the perceived unpleasant smell our bodies can give off when bacteria that live on the skin break down sweat into acids. People who are obese, those who regularly eat spicy foods, as well as individuals with certain medical conditions, such as diabetes, are more susceptible to having body odor. People who sweat too much, such as those with hyperhidrosis, may also be susceptible to body odor. However, often the salt level of their sweat is too high for the bacteria to break down. Sweat is the rapid multiplication of bacteria in the presence of sweat and their breaking down of sweat into acids that eventually causes the unpleasant smell.

32. Causes :- Body odor is caused by bacteria breaking down sweat and is largely linked to the apocrine glands. Most body odor comes from these. These glands are found in the breasts, genital area, eyelids, armpits, and ear. In the ear, they help form earwax. Apocrine glands in the skin and the eyelids are sweat glands. Most of the apocrine glands in the skin are located in the groin, arm pits. In the skin, they usually have an odor. The apocrine glands are mainly responsible for body odor because the sweat they produce is high in protein, which bacteria can break down easily

33. Prevention :- Wash daily with water : Have a shower or bath at least once a day. since warm water helps kill off bacteria that are present on the skin. Clothing: Natural fibers allow your skin to breathe, resulting in better evaporation of sweat. Eg :- Cotton Avoid spicy foods: Curry, garlic, and other spicy foods have the potential to make some people's sweat more pungent. A diet high in red meat may develop more rapid body odor. Aluminum chloride : It is main ingredient in antiperspirants. Antiperspirant : these are personal hygiene products designed to control sweating and body odour safely and effectively. Deodorant : these are used to eliminate bad odour which is caused by sweating , applied locally on the surface of the body

34. HAIR A hair can be defined as a slender, thread-like outgrowth from a follicle in the skin of mammals. It is Composed mainly of keratin, it has three morphological regions — the cuticle Medulla Cortex.

35. The two main structures of hair are :-

36. Anatomy of hair

37. Cuticle The cuticle comprises 8-10 layers of flat overlapping translucent cells - meaning they are essentially transparent, like window glass. The primary role of the cuticle is to protect the underlying cortex. The cells that make up the cuticle are stabilised and held in place by disulphide bonds. The health of the cuticle is vital because it affects the hydration, texture, feel and glossiness/shine of hair. The surface of the cuticle is hydrophobic (water-hating), which means that the cuticle readily binds to oils and other hydrophobic substances. Hair sprays, mousses and gels all act directly on the cuticle. The cuticle is physically damaged by brushing, especially when wet. Products such as conditioners and oils soften the cuticle making it less brittle, reducing loss. Due to its protective role, the cuticle is considered the most critical health indicator by many hair scientists.

38. CORTEX The cortex is the largest constituent of hair, making up ~75% by weight. The cortex is in the centre of each hair fibre and consists of long, tightly packed keratin spindles stabilised by disulphide bonds. These keratin spindles are arranged in a hierarchy, starting with the smallest structure, the keratin proteins themselves, to the largest and final structure, the cortex itself. The cortex gives hair its strength and is also home to melanin granules. These are packets of pigment that are responsible for your hair colour. The cortex is also responsible for giving hair its shape and texture, resulting in your hair being either straight, wavy, curly or kinky. Everyday hair care products that can damage the cortex include perming, curling, straightening and bleaching solutions. The chemicals within these products penetrate your hair and destabilise the disulphide bonds within the cortex, both weakening and disorganising it.

39. MEDULLA The medulla is located at the centre of many but not all hair fibres - typically within thicker, coarser terminal hair. It is believed to contribute in higher volume/ body to the hair. The medulla may provide thermo-regulatory properties to hair with regard to the airspaces within the medulla. If present, the medulla may also be discontinuous, meaning that it is patchy and does not run through the entire hair fibre length. The medulla has a higher lipid content and has reduced disulfide bonds in comparison to other hair structures. The medulla is very porous, meaning that it contains large voids containing air or possibly water and oils .

40. Other Components :- Hair bulb : The bulbous part at the bottom of the hair follicle that produces new hair cells. The cells in the hair bulb divide rapidly and push older cells up the follicle. Dermal papilla : A population of cells in the skin that regulates hair follicle development and growth. Arrector pili muscle : A small, involuntary muscle that ensures hair grows perpendicular to the skin. Sebaceous gland : A small, sack-shaped gland that releases an oily substance onto the hair follicle to protect it from becoming brittle.

41. STRUCTURE OF HAIR

42. HAIR GROWTH CYCLE

43. ANAGEN PHASE The anagen is the active growth phase in which the follicle enlarges and takes the original shape and the hair fiber is produced. Almost 85–90% of all scalp hairs are in anagen. Mitosis is occurring Hair grows between 1 to 1.5 cm per month. Hair bulb is round and full & contains melanin in it.

44. CATAGEN PHASE At the end of anagen, mitotic activity of the matrix cells is diminished and the follicle enters a highly controlled involutionary phase known as catagen. Catagen lasts approximately 2 weeks in humans, regardless of the site and follicle type. Transition stage Mitosis stops

45. TELOGEN PHASE The telogen stage is defined as the duration between the completion of follicular regression and the onset of the next anagen phase. Resting phase Telogen stage lasts for 2–3 months. Approximately 10–15% of all hair is in telogen stage. Hairs fall out approx 50-80 hairs per day are lost.

46. EXOGEN PHASE It is the final stage of the hair growth cycle, when hair sheds and new hair grows: During the exogen phase, old hair falls out as new hair grows in the hair follicle. This phase can last up to five months. It marks the end of the telogen phase and the beginning of the anagen phase . New hair pushes the old hair out, causing it to fall out. A healthy scalp sheds 50–100 hairs per day. This is normal and temporary, unless there's an underlying condition or genetic cause.