Although skin aging has not been related to many health complications, it has aesthetic issues. Some of the common symptoms of skin aging are changes in the skin texture (rough, dry, and itchy), discoloration, reduction in skin elasticity, and enhanced susceptibility to bruises.
Scientists have formulated various nano-based products to reverse, prevent or decelerate the process of skin aging. This article discusses some of the nanotechnology-based approaches to reverse skin aging.
The Human Skin
The skin is the outermost cutaneous membrane that covers the body’s surface and provides protection from the external environment. It is primarily classified into three layers, i.e., the outer layer (epidermis), middle layer (dermis), and innermost layer (subcutaneous).
The outer epidermis layer predominantly contains keratinocytes without any blood vessels. The dermis layer contains cellular components and an extracellular matrix. The main components of the dermis include collagen fibers (tensile strength), elastic fibers (elasticity and resilience), glycoproteins (e.g., integrins, and fibulins), and glycosaminoglycans (hydration).
Key Factors Associated with Skin Aging
Studies have shown that both endogenous and exogenous factors are associated with the process of skin aging. Intrinsic aging occurs due to changes in the epithelial layers, while extrinsic aging is caused by the abnormal accumulation of elastic fibers in the dermis middle layer. Intrinsic aging is governed by the genetic traits of an individual, along with changes in their hormones and cellular mechanisms.
Some of the hormones related to skin functions are testosterone, estrogen, melatonin, cortisol, and thyroxine. For instance, hypoestrogenism occurs in postmenopausal women, making their skin thinner and drier. Oxidative stress, caused due to continual production of reactive oxygen species (ROS), leads to mitochondrial DNA damage and loss of skin elasticity.
Scientists have stated that mitochondrial DNA damage and shortening of telomeres are highly correlated to aging. A decrease in collagen production with aging leads to sagging of skin.
One of the factors associated with extrinsic aging is prolonged sun exposure. The UV rays change the cellular component of the skin and cause discoloration, loss of skin elasticity, deep wrinkling, and loss of hydration. Other lifestyle-related factors, such as sleep, diet, exercise, and smoking, are linked with skin aging. Scientists revealed that smoking damages the collagen and elastic fibers present in the dermis, making the skin loose and dry.
Nanotechnology and Anti-Aging Products
Some of the advantages of nanocosmeceuticals include enhanced efficacy and stability of the active ingredients in the skin product. Studies have shown that nanoparticle-based cosmeceutical formulations exhibit superior skin permeability and cause minor side effects.
Scientists have developed several nanoparticle formulations for the cosmetic industry. Some of the nanocarriers developed for anti-aging applications are as follows:
This is a popularly used nanodelivery system that significantly enhances the efficacy of a drug and reduces its side effects. These nanoparticles possess an aqueous core with phospholipid bilayers surrounding them. Liposomes are regarded as an ideal nanocarrier for skincare formulations because of their excellent penetration capacity and biocompatibility. When applied, liposomes bind to the skin cell membranes and release the active ingredients into the cell, which combats wrinkles and promotes the regeneration of skin cells. Many popular high street brands have developed liposome-based anti-aging formulations.
Niosomes are vesicle-like structures, composed of non-ionic surface-active agents. A study related to entrapping rice bran components with antioxidant properties into niosomes revealed promising anti-aging properties.
Typically, ethosomes are used to transport drugs deep into the dermis. These small, malleable nanostructures are used to deliver drugs via the transdermal route. One of the most advantageous properties of this nanostructure is that it can easily penetrate smaller pores of the skin.
In a recent study, scientists loaded rosmarinic acid into ethosomes which exhibited a significant anti-aging effect. This is because ethosomes enhanced the penetration of rosmarinic acid into the skin, and this prevented the degradation of elastin and collagen.
These are polymeric nanoparticles where active ingredients are covalently attached to the walls. Nanocapsule-based formulations containing various active compounds, for example, Vitamin E, antioxidants, retinoids, and β-carotene, have been developed for effective and targeted delivery. The development of an anti-wrinkle cream by encapsulating Vitamin C offers a slow release of the active compound for a prolonged time, preserving skin health for a longer periods.
As the same suggests, these are spherical nanoparticles in which active compounds are distributed throughout the matrix. Poly D, L lactic-co-glycolic acid (PLGA) polymer is popularly used for the development of nanospheres.
Research has shown that Vitamin C-loaded PLGA nanospheres could penetrate melanocytes and fibroblasts in the skin and gradually release the compound. Vitamin C reduces skin blemishes and wrinkles by promoting the formation of collagen and its antioxidant properties reduce ROS levels. Therefore, this formulation has proved to be an effective anti-aging and anti-wrinkle agent.
Scientists have prepared nanoemulsions of grapeseed oil and studied its efficacy in preventing skin aging. They observed that the antioxidant property of grapeseed oil helped to keep the skin healthy. This technology has been used by many brands to develop an effective treatment to cure wrinkles and fine lines of the skin.
Fullerene is a carbon allotrope, composed of spherically attached carbon atoms. A recent study reported that fullerene nanocapsules containing ascorbic acid and Vitamin E exhibited a protective function against premature skin aging.
The rapid advancements in nanocosmeceuticals promise many innovative skin formulations that could effectively reverse skin aging. Researchers are set to discover new bioactive compounds and phytochemicals with excellent anti-aging and antioxidant properties in the future. Additionally, the development of novel nanocarriers will ensure targeted delivery of these compounds and protect them from degradation for a prolonged period.