China
Africa
Explore chapters and articles related to this topic
Oxidative Stress-Protective/Anti-Melanogenic Effects of Loliolide
Published in Debarshi Kar Mahapatra, Cristóbal Noé Aguilar, A. K. Haghi, Natural Products Pharmacology and Phytochemicals for Health Care, 2021
Francisco Torrens, Gloria Castellano
The GAs are considered as a representative biosource to be applied for the preparation of pharmaceutical, nutraceutical, and cosmeceutical products. Prasiola japonica is freshwater GAs with a lot of NCs, for example, MTL g-lactone (-)-loliolide (cf. Figure 7.1), methylpyrazine, 1-hydroxy-2-propanone, diisopropylamine, 1,6-dihydro-6-oxo-3-pyridinecarboxamide, mannitol, mannose, and glucitol, according to gas chromatography/mass spectrometric (GC/MS) analysis. Of them, loliolide results in an active component in GAs with a number of bioroles (e.g., anti-aging, antiviral, AIAs). However, the effects of freshwater GAs components, loliolide, and Pj-EE, on the skin were not studied extensively. The OS-protective effects of loliolide and Pj-EE were investigated in human keratinocyte HaCaT cells [29]. To do this, the effects of loliolide and Pj-EE on the expression of AO protein nuclear factor (erythroid-derived 2)-like 2 (NRF2)-Kelch-like ECH-associated protein 1 (KEAP1) signaling pathway proteins were confirmed by Western blot. The expression of genes encoding matrix metalloproteinases (MMPs) was confirmed by reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR analyses, and cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Mouse melanoma B16F10 cells were used to assess AMA of loliolide and Pj-EE, measuring the level of melanin content and secretion. The expression of the melanocortin-1 receptor (MC1R) proteins related to melanogenesis was confirmed by Western blot.
Active Nanoparticle Targeting: Current Status and Future Challenges
Published in Sandeep Nema, John D. Ludwig, Parenteral Medications, 2019
Siddharth Patel, Janni Mirosevich
The way in which targeting moieties/ligands on nanoparticles can potentially adversely affect cell biology is another essential factor when evaluating targeted delivery systems. The melanocortin 1 receptor (MC1R) belongs to a family of five G protein-coupled melanocortin receptors (MC1R–MC5R) and is highly expressed on the surface of melanomas (Rosenkranz et al. 2013). As such, a number of highly specific and selective ligands against MC1R have been developed (Cai et al. 2006; Mayorov et al. 2006; Koikov et al. 2003). These ligands have been used for targeted imaging agents, targeted polymer-based micelles, and polymeric gene delivery nanoparticles (Durymanov et al. 2012; Barkey et al. 2011; Tafreshi et al. 2012; Barkey et al. 2013). However, MC1R activation is known to be involved in proliferation of melanoma cells (Rosenkranz et al. 2013). It is also known that EGF binding to EGFR activates signaling pathways that stimulate cell proliferation and survival (Master and Sen Gupta 2012; Wang 2012). Therefore, because many ligands are known to activate signaling pathways that promote cancer growth, downstream molecular pathways must be considered in order to ensure that nanoparticle ligand binding does not have unfavorable effects on the cells and tissues being treated.
Flavonoids from Quercus Genus: Applications in Melasma and Psoriasis
Published in Tatjana Stevanovic, Chemistry of Lignocellulosics: Current Trends, 2018
Esquivel-García Roberto, Velázquez-Hernández María-Elena, Valentín-Escalera Josué, Valencia-Avilés Eréndira, Rodríguez-Orozco Alain-Raimundo, Martha-Estrella García-Pérez
UV radiation (UVA, UVB, etc.), promotes KCs to induce melanocyte proliferation and melanogenesis by secreting fibroblast growth factor (bFGF), nerve growth factor (NGF), endothelin-1 (ET-1), IL-1, inducible nitric oxide synthase (iNOS) and proopiomelanocortin (POMC)-derived peptides such as melanocyte- stimulating hormone (MSH) and adrenocorticotrophic hormone (ACTH). POMC- derived peptides and MSH receptors participate in the paracrine interaction between KCs and melanocytes. The binding of melanocortin to the MC-1 receptor (MC1R) expressed in melanocytes activates adenylate cyclase and increases cyclic adenosine monophosphate (cAMP) formation. cAMP signal transduction pathway, which results in the activation of protein kinase A (PKA) induces melanogenesis. Another signal transduction pathways involved in melanogenesis are protein kinase C (PKC) activation due to the formation of diacylglycerols, and nitric oxide (NO) production accompanied by cyclic guanylate monophosphate (cGMP) synthesis (Lee 2015, Kwon et al. 2016).
Antioxidant and anti-tyrosinase activities of quercetin-loaded olive oil nanoemulsion as potential formulation for skin hyperpigmentation
Published in Journal of Dispersion Science and Technology, 2022
Cristiane C. Silva, Rogério B. Benati, Taís N. C. Massaro, Karina C. Pereira, Lorena R. Gaspar, Priscyla D. Marcato
Since melasma and other hyperpigmentation disorders are frequent in regions of the body that are exposed to the sun, ultraviolet radiation (UV) is considered a key factor for their development. The radiation on the skin stimulates the production of melanocyte-stimulating hormone (α-MSH), which in turn induces the modification of the melanocortin receptor (MC1R), leading to an increase in the transcription factor associated with melanogenesis (MITF). This factor activates tyrosinase and tyrosinase-related proteins (TRP) in the Golgi complex, leading to greater production of the pigments eumelanin and pheomelanin.[12,13] Reactive oxygen species (ROS) are also important mediators for the activation of the pathway. Therefore, there is a relationship between oxidative stress and hyperpigmentation disorders.[13,14]