Tyrosinase

Teucrium chamaedrys L. is a typical European-Mediterranean species of the genus Teucrium. Among the phenolic compounds belonging to phenylethanoid glycosides (PGs), teucrioside (TS) is only found in this species, and it was previously demonstrated to be produced by in vitro-elicited cell cultures at levels higher than those found in leaves. However, T. chamaedrys cell suspension extracts (Cell-Ex) and pure TS have not been investigated yet for any biological effects. In this study, we evaluated the antioxidant and anti-melanogenesis activity of both Cell-Ex and TS in B16-F10 mouse melanoma cells...

The incidence of skin-related neoplasms has generally increased in recent years. Melanoma arises from malignant mutations in melanocytes in the basal layer of the epidermis and is a fatal skin cancer that seriously threatens human health. Isoflavones are polyphenolic compounds widely present in legumes and have drawn scientists' attention, because they have good efficacy against a variety of cancers, including melanoma, without significant toxic side effects and resistance. In this review article, we summarize the research progress of isoflavones in melanoma, including anti-melanoma roles and mechanisms of isoflavones via inhibition of tyrosinase activity, melanogenesis, melanoma cell growth, invasion of melanoma cells, and induction of apoptosis in melanoma cells...

A novel series of 4-nitrophenylpiperazine derivatives (4a-m) was designed and synthesized as potential tyrosinase inhibitors. Comprehensive characterization using 1 H-NMR, 13 C-NMR, CNH, and IR techniques was performed for all target compounds. Subsequently, the derivatives were evaluated for their inhibitory activity against tyrosinase. Among them, compound 4l, featuring an indole moiety at the N-1 position of the piperazine ring, exhibited a significant tyrosinase inhibitory effect with an IC50 value of 72...

INTRODUCTION: Although checkpoint inhibitors (CPIs) have improved outcomes for patients with metastatic melanoma, those progressing on CPIs have limited therapeutic options. To address this unmet need and overcome CPI resistance mechanisms, novel immunotherapies, such as T-cell engaging agents, are being developed. The use of these agents has sometimes been limited by the immune response mounted against them in the form of anti-drug antibodies (ADAs), which is challenging to predict preclinically and can lead to neutralization of the drug and loss of efficacy...

Lantana camara is widely known as a garden plant, but its use for various medicinal purposes is widespread in traditional medicine. In the frame of this study, L. camara was subjected to several different extraction techniques, including supercritical carbon dioxide extraction, accelerated solvent extraction (ASE), homogenizer-assisted extraction, microwave-assisted extraction, ultrasound-assisted extraction, maceration, and Soxhlet extraction. The investigation encompasses the analysis of the chemical composition alongside assessments of biological activities, such as antioxidant and enzyme-inhibition potential and cytotoxicity of the obtained extracts...

Topicals and chemical peels are the standard of care for management of facial hyperpigmentation. However, traditional therapies have come under recent scrutiny, such as topical hydroquinone (HQ) has some regulatory restrictions, and high concentration trichloroacetic acid (TCA) peel pose a risk in patients with skin of colour. The objective of our research was to identify, investigate and elucidate the mechanism of action of a novel TCA- and HQ-free professional-use chemical peel to manage common types of facial hyperpigmentation...

Environmental concerns are driving interest in postpetroleum synthetic textiles produced from microbial and fungal sources. Bacterial cellulose (BC) is a promising sustainable leather alternative, on account of its material properties, low infrastructure needs and biodegradability. However, for alternative textiles like BC to be fully sustainable, alternative ways to dye textiles need to be developed alongside alternative production methods. To address this, we genetically engineer Komagataeibacter rhaeticus to create a bacterial strain that grows self-pigmenting BC...

Tyrosinase is capable of oxidizing tyrosine residues in proteins, leading to intermolecular protein cross-linking, which could modify the protein network of food and improve the texture of food. To obtain the recombinant tyrosinase with microbial cell factory instead of isolation tyrosinase from the mushroom Agaricus bisporus , a TYR expression cassette was constructed in this study. The expression cassette was electroporated into Trichoderma reesei Rut-C30 and integrated into its genome, resulting in a recombinant strain C30-TYR...

Research on new ingredients that can prevent excessive melanin production in the skin while considering efficacy, safety but also environmental impact is of great importance to significantly improve the profile of existing actives on the market and avoid undesirable side effects. Here, the discovery of an innovative technology for the management of hyperpigmentation is described. High-throughput screening tests on a wide chemical diversity of molecules and in silico predictive methodologies were essential to design an original thiopyridinone backbone and select 2-mercaptonicotinoyl glycine (2-MNG) as exhibiting the most favorable balance between the impact on water footprint, skin penetration potential and performance...

The present study aimed to investigate the chemical profile, antioxidant, and enzyme inhibition properties of extracts from fruits and aerial parts (leaves and twigs) of Tamarix aphylla and T. senegalensis. Hexane, dichloromethane, ethyl acetate (EtOAc), and methanol extracts were prepared sequentially by maceration. Results revealed that EtOAc extracts of T. senegalensis and T. aphylla fruits contained the highest total phenolic content (113.74 and 111.21 mg GAE/g) while that of T. senegalensis (38.47 mg RE/g) recorded the highest total flavonoids content...

CONTEXT: Hyperpigmentation, a common skin condition marked by excessive melanin production, currently has limited effective treatment options. OBJECTIVE: This study explores the effects of Tao-Hong-Si-Wu decoction (THSWD) on hyperpigmentation and to elucidate the underlying mechanisms. MATERIALS AND METHODS: We employed network pharmacology, Mendelian randomization, and molecular docking to identify THSWD's hub targets and mechanisms against hyperpigmentation...

Melanocyte differentiation is orchestrated by the master regulator transcription factor MITF. However, its ability to discern distinct binding sites linked to effective gene regulation remains poorly understood. This study aims to assess how co-activator acetyltransferase interacts with MITF to modulate their related lysine action, thereby mediating downstream gene regulation, including DNA affinity, stability, transcriptional activity, particularly in the process of shell pigmentation. Here, we have demonstrated that the CgMITF protein can be acetylated, further enabling selective amplification of the melanocyte maturation program...

Trigonelline (TRG) is a natural polar hydrophilic alkaloid that is found in many plants such as green coffee beans and fenugreek seeds. TRG potentially acts on multiple molecular targets, including nuclear factor erythroid 2-related factor 2 (Nrf2), peroxisome proliferator-activated receptor γ, glycogen synthase kinase, tyrosinase, nerve growth factor, estrogen receptor, amyloid-β peptide, and several neurotransmitter receptors. In this review, we systematically summarize the pharmacological activities, medicinal properties, and mechanistic actions of TRG as a potential therapeutic agent...

Tyrosinase serves as the key enzyme in melanin biosynthesis, catalyzing the initial steps of the pathway, the hydroxylation of the amino acid L-tyrosine into L-3,4-dihydroxyphenylalanine (L-DOPA), followed by the subsequent oxidation of L-DOPA into dopaquinone (DQ), and it facilitates the conversion of 5,6-dihydroxyindole-2-carboxylic acid (DHICA) into 5,6-indolequinone-2-carboxylic acid (IQCA) and 5,6-dihydroxy indole (DHI) into indolequinone (IQ). Despite its versatile substrate capabilities, the precise mechanism underlying tyrosinase's multi-substrate activity remains unclear...

Cancer immunotherapy as a promising anti-cancer strategy has been widely studied in recent years. Stigmasterol (STIG), a phytosterol, is known to have various pharmacological effects, including anti-inflammatory effects. However, the pharmacological role of STIG on melanoma immunotherapy has not been investigated. The present study demonstrates the anti-melanoma potency of STIG through the regulation of PD-L1 levels. The results reveal that STIG reduces reactive oxygen species (ROS) levels induced by hydrogen peroxide and increases glutathione levels decreased by α-MSH in B16F10 cells...

The cultivation of Crocus sativus L. to obtain the saffron spice generates a large amount of biowaste, constituted mainly by the flower's tepals. The aim of this work was to evaluate the antioxidant and dermo-protective effect of a complex methanolic extract of C. sativus tepals. The extract's major phenolic content was analyzed using ultra-high performance liquid chromatography with electrospray ionization, coupled with quadrupole-time-of-flight-mass spectrometry (UHPLC-ESI-QTOF-MS). Then, the antioxidant in vitro activity of the extract was studied and related to their chemical composition...

The total melanin synthesis in the skin depends on various melanogenic factors, including the number of viable melanocytes, the level of melanogenic enzymes per cell, and the reaction rate of the enzymes. The purpose of this study is to examine the effects of L-cysteine (L-Cys), L-ascorbic acid (L-AA), and their derivatives on the tyrosinase (TYR) activity and autoxidation of L-3,4-dihydroxyphenylalanine (L-DOPA) in vitro and the viability and melanin synthesis of B16/F10 cells under different conditions. L-Cysteinamide (C-NH2 ), glutathione (GSH), L-Cys, L-AA, and N -acetyl L-cysteine (NAC) inhibited the catalytic activity of TYR in vitro...

The presence of a hydration layer in humid and underwater environments challenges adhesive-substrate interactions and prevents effective bonding, which has become a significant obstacle to the development of adhesives in the industrial and biomedical fields. In this study, ultrahigh-molecular-weight (UHMW) silk-elastin-like proteins (SELP) with 3,4-dihydroxyphenylalanine (DOPA) converted from tyrosine residues by tyrosinase exhibited excellent adhesive properties on different interfaces, such as glass, aluminum, wood, polypropylene sheets, and pigskin, under both dry and wet conditions...

Guava ( Psidium guajava ) is a plant widely distributed in tropical and subtropical regions. Its leaves contain a large amount of physiological molecules such as flavonoid, sesquiterpene, triterpenoid, coumarin, alkaloid, and tannin molecules with antioxidative and anti-inflammatory effects. In this study, the use of concentrated P . guajava leaf extract molecules as a functional natural material was evaluated by confirming the extract's antioxidative, antibacterial, tyrosinase activity inhibition, and collagenase activity inhibition effects and its trans-2-nonenal removal ability...

In the pursuit of bioactive compounds with health benefits from food and medicinal plants, optimization of process to reduce solvent, raw material, energy and time consumption has been a valuable research objective. Sustainable management and efficient use of natural resources are of critical importance for sustainability goals. In this manner, microwave extraction of red cabbage which has been a mass cultivated plant for food purposes, was optimized for maximizing acetylcholinesterase, butyrylcholinesterase, tyrosinase inhibitory activity and bioactive content...