Preface

Mother Nature has always been the treasure trove for biologically active compounds that helped humanity to survive and thrive. Medicinal plants have played a major role in the development of human civilizations. Since antiquity, humans have been searching for natural sources to cure diseases, and found their target in medicinal plants. The Egyptian, Greek, Indian, Chinese, and Aztec civilizations relied heavily on the use of medicinal plants to cure human and animal ailments. Medicinal plants have been used to treat all types of disorders, including cardiovascular, digestive, skin and kidney disorders. Skin disorders differ from other disorders by being external, can be detected by the naked eye, medicinal plant extracts can be easily applied to the disorders, and the healing effect can be easily tracked. Skin is the largest organ in the human body and the first line of defense against traumas, infections and radiation. Skin is a dynamic organ with millions of cells dying and regenerating regularly. It is affected by a plethora of disorders and should be treated to avoid the spread of invasion to internal organs.

Medicinal plants have been used to treat skin disorders and to improve skin condition. They have also been used in cosmetic preparations to remove wrinkles, black spots and provide a radiant appearance. In the current book, we take the reader on an enjoyable journey of medicinal plants treating skin-related disorders. The first chapter reveals “How to protect skin from harmful solar radiation.” Pathologically solar radiation having UVA (320–400 nm) and UVB (290–320 nm) wavelengths may lead to serious hazards, especially to the skin. On one side, sunlight is essential for Vit D creation but on the other side, continuous exposure to it may lead to risk from sunburn to skin cancer. UV radiation can produce harmful compounds called free radicals or reactive oxygen species or ROS, which leads to skin cancer and premature aging. Traditionally herbal formulations and herbal extracts have been used as a sunscreen for photoprotection for a long time and are considered more vigorous compared to allopathic topical preparations due to their complex composition and high sun protection factor or SPF value. Vitamins C and E and flavonoids herbs not only show antioxidant properties but also indicate a strong potential against adverse skin reactions ensuing UV exposure. The second chapter clarifies “Natural products and burns: A tough case to crack”. Burns are a type of skin injury that occurs due to close contact with a heat source or corrosive chemicals. The use of natural products to treat burns dates back to ancient civilizations. In this chapter, naturally derived products from plants, animals and fungal sources are discussed. The extraction and preparation methods, burn healing mechanisms, clinical studies, and pharmaceutical formulation are covered. The third chapter discusses “Wound healing”. Wound healing is quite a complicated process in the human body, consisting of the action of constricting injured blood vessels, activating the immune system, angiogenesis, remodeling, etc. Under intensive mechanical stress, a fibrotic scar, which is unfavorable with respect to the beauty of the skin, can be formed to patch the wound. Moreover, chronic wounds due to the disruption in wound healing is another clinical problem for patients with diabetes or vascular diseases. Of note is that natural remedies, especially natural products, are demonstrated to be able to elicit certain positive effects on many aspects of wound healing. The fourth chapter discusses “The role of natural products in the management of pigmentary anomalies”. The skin is one of the most important organs of the human body. Dermatological ailments and pathologies are of importance for public health because, since to represent physical damages, they manifest emotional and psychological repercussions, which sometimes present higher costs than the former. Some of the most important pathologies are eczema, psoriasis, acne, rosacea, vitiligo, pyoderma, scabies, tinea capitis, dermatitis, reactions of poisonous insect or reptile bites hives, pigmentary anomalies, and injuries such as burns and scars. These skin and subcutaneous disorders were the 4 ^th leading cause of nonfatal disease burden worldwide in 2010 and 2013, emphasizing the role of dermatology in the ever-expanding field of global health. The fifth chapter deals with “Treatment of scabies with herbal medicines”. Scabies has been acknowledged as a neglected tropical disease by the world health organization. Scabies is the most stereotypically occurring skin disease in developing countries, greatly contributing to mortality and morbidity worldwide. More than 0.3 billion of the global population is getting affected with a high prevalence rate in tropical countries that have poor resources. Skin is the largest organ of the body which acts as the instinctive fencing between external and internal conditions playing a significant role in some crucial biological processes like protecting from chemical and mechanical injuries. Scabies also cause a wide range of skin ailments such as abscesses, impetigo, and cellulitis, consequently leading to critical abnormal conditions like rheumatic heart disease, septicemia, and kidney disease. The sixth chapter summarizes “Back to the Roots: Natural cosmetics and their future applications”. Numerous concerns have been raised on the side effects of the prolonged usage of synthetic compounds in cosmetics production, including skin damage due to inflammations, rashes, and itching, just to mention a few. These skin side effects have been reported to be linked to the breakdown of homeostasis of the repair system against deoxyribonucleic acid (DNA) and tissue destruction and these can lead to accelerated aging, melanogenesis, cell senescence or even cancer of the skin. Efforts to overcome these problems associated with synthetic cosmetics have led to the use of natural cosmetics of plant and animal origin. The seventh chapter discusses “Natural products and nanoparticle skin delivery”. The use of synthetic products is usually associated with side effects, while natural products are also not completely without demerits, including poor solubility and/or stability. The application of nanoparticles is cutting across all human endeavors, with product development not being an exception. Skin disease treatment is one aspect of medicine that is as distinct as it usually involves topical application, and eventual absorption onto the skin surface. The use of nanoparticles has proven to be an effective way to solve the problems associated with the use of natural products in skin care and treatment. The eighth chapter deals with “Smart drug delivery systems for the topical administration of natural products”. The effectiveness of natural products in the treatment and prevention of human diseases has been widely demonstrated by the world scientific community. The skin is often subject to the onset of pathologies induced by chemical or physical insults, such as the collateral effects of certain drugs, tumors, or photo-induced damage. The current treatments of skin diseases are focused, in most cases, on the systemic or oral administration of the drugs, since the classic topical administration does not allow it to reach the pharmacological objectives.

We covered in this book a wide array of skin disorders and how to treat them using medicinal plants. We included researchers from different countries to discuss their experience in using medicinal plants for the treatment of skin disorders. This book will guide researchers all over the world to understand the value of medicinal plants in treating skin disorders and how to move forward in their research.