Just like every other part of the organism, the skin ages as a result of the passage of time. That process is called chronologic or intrinsic aging. However, skin is also exposed to external insults, such as UV radiation, which is the most influential extrinsic factor in skin aging, causing so called photoaging or extrinsic skin aging. Photoaging is a cumulative process which depends on the deg...

Retinoids are a group of substances comprising vitamin A and its natural and synthetic derivatives. Retinoids were first used in dermatology in 1943 by Straumfjord for acne vulgaris. Since that time, retinoids have been utilized in the management and treatment of various skin conditions, including photoaging. Photodamage of the skin occurs as a consequence of cumulative exposure to solar ultrav...

Physiological processes, as aerobic metabolism and inflammatory response, generate reactive oxygen species (ROS) that may induce cellular injury when their amount is increased and antioxidant defense mechanisms are overwhelmed. Also, ROS are generated following UV skin irradiation able to deplete the natural antioxidant defenses in the skin. The increase in exposure to UV may lead to photoaging...

The phenomenon of skin aging may be categorized broadly into photoaging caused by exogenous factors and physiological aging induced by endogenous factors. A near-infrared diffuse reflectance (NIR-DR) spectroscopy method was recently proposed for non-invasive evaluation of changes that occur within the skin of hairless mice that were divided into an ultraviolet-B (UVB)-irradiated group (photoag...

Ultraviolet irradiation directly affects the skin and promotes photoaging by causing depletion of antioxidative enzymes. We recently reported that M1/M2 macrophage ratio is altered in photo-aged skin. However, relationship between balance expression enzymes has not been fully investigated. Here, we show skewing related to reduction enzyme peroxiredoxin 4 (PRDX4) it may lead photoaging. performe...

Photoaging refers to the effects of long-term ultraviolet (UV) exposure and sun damage superimposed on intrinsically aged skin. The clinical signs associated with photoaging include dyspigmentation, laxity, a yellow hue, wrinkles, telangiectasia, a leathery appearance, and cutaneous malignancy. These changes often occur gradually as a person ages but can develop earlier if extensive UV exposure...

The significant increase in life expectancy is closely related to the growing interest in the impact of aging on the function and appearance of the skin. Skin aging is influenced by several factors, and solar ultraviolet (UV) irradiation is considered one of the most important causes of skin photoaging. The aim of this study was to examine the anti-photoaging role of porphyra-334 from Porphyra ...

Skin-targeted ultrasound is a noninvasive technique that has been extensively used to evaluate age-related dermal changes, and the presence of a subepidermal low-echogenic band (SLEB) has been related to chronic UVR exposure in several studies. Since SLEB echogenicity is photoage-related, the aim of this study was to evaluate, through ultrasound imaging, the effects on skin photoaging of mesoth...

Solar ultraviolet (UV) radiation is a main extrinsic factor for skin aging. Chronic exposure of the skin to UV radiation causes the induction of matrix metalloproteinases (MMPs), such as MMP-1, and consequently results in alterations of the extracellular matrix (ECM) and skin photoaging. Flavonoids are considered as potent anti-photoaging agents due to their UV-absorbing and antioxidant propert...

Introduction Ultraviolet radiation (UVR) in sunlight is the most important cause of skin damage and aging.'"' This form of radiation causes skin aging by several mechanisms, including free-radical generation, DNA damage, collagen breakdown, the induction of immune defects, and cell death.'-5 In addition, repeated damage to the skin by sunburn is a primarily risk factor for the development of cu...