Aims: The 2, 3, 5, 4'-tetrahydroxystilbene-2-O-beta-D-glucoside (THSG), a water-soluble active component extracted from dried tuber root of Polygonum multiflorum, has been found to induce pigmentation in B16 cells, but the details of the underlying mechanism remain unknown. The present study was conducted to investigate the mechanism of stimulatory effect of THSG on melanogenesis using B16F1 melanoma cells.
Main Methods: Several experiments were performed in B16F1 melanoma cells. We studied melanin content, tyrosinase activity, cell viability, and performed reverse transcription polymerase chain reaction and Western blots for proteins involved in melanogenesis.
Key Findings: THSG increased the melanin content and tyrosinase activity in a concentration-dependent manner and treatment with 10 microg/ml THSG enhanced the expression of tyrosinase time-dependently in B16 cells. We then investigated whether THSG influences the expression of microphthalmia-associated transcription factor (MITF), which is required for tyrosinase expression. THSG was found to induce sustained MITF up-regulation and cAMP response element (CRE) binding protein (CREB) activation, suggesting that THSG-mediated MITF activation may be cAMP dependent. Furthermore, Western blot analysis revealed that THSG elevated the level of phosphorylation of p38 mitogen-activated protein kinase (p38 MAPK) significantly at 1-6 h; a p38 MAPK inhibitor, SB203580, almost completely attenuated the THSG-mediated up-regulation of melanin synthesis and induction of MITF and tyrosinase expression.
Significance: THSG exerts its stimulatory effect on melanogenesis by MAP kinase activation and MITF-induction of tyrosinase.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.lfs.2009.05.022 | DOI Listing |
Nat Commun
January 2025
The Kennedy Institute of Rheumatology, University of Oxford, Oxford, UK.
Loss of IFNγ-sensitivity by tumours is thought to be a mechanism enabling evasion, but recent studies suggest that IFNγ-resistant tumours can be sensitised for immunotherapy, yet the underlying mechanism remains unclear. Here, we show that IFNγ receptor-deficient B16-F10 mouse melanoma tumours are controlled as efficiently as WT tumours despite their lower MHC class I expression. Mechanistically, IFNγ receptor deletion in B16-F10 tumours increases IFNγ availability, triggering a remodelling of the immune landscape characterised by inflammatory monocyte infiltration and the generation of 'mono-macs'.
View Article and Find Full Text PDFFree Radic Biol Med
December 2024
Centre for Pre-clinical Studies, CSIR-North East Institute of Science and Technology (NEIST), Jorhat, Assam, 785006, India; AcSIR-Academy of Scientific and Innovative Research, Ghaziabad, Uttar Pradesh, 201002, India. Electronic address:
Akhuni, an ethnic food of northeast India, induces ROS-mediated apoptosis in cancer cells. This is the first report on the anticancer potential of Akhuni. Akhuni is a traditional fermented soybean product known for its umami taste and delicacy, commonly used in Northeast India's cuisine.
View Article and Find Full Text PDFInt J Biol Sci
January 2025
Cancer Center and Center of Reproduction, Development & Aging, Institute of Translation Medicine, Faculty of Health Sciences, University of Macau, Taipa, Macau, China.
Cancer radical surgery is the primary treatment for melanoma, but almost all malignant melanoma patients get recurrence and metastasis after surgery and are eventually dead. This clinical dilemma appeals to better drugs for post-surgery therapy. Artemisinin is a safe and effective antimalarial drug used in the clinic for decades.
View Article and Find Full Text PDFFront Immunol
December 2024
Myeloid Therapeutics, Inc., Cambridge, MA, United States.
Introduction: The approval of chimeric antigen receptor (CAR) T cell therapies for the treatment of B cell malignancies has fueled the development of numerous cell therapies. However, these cell therapies are complex and costly, and unlike in hematological malignancies, outcomes with most T cell therapies in solid tumors have been disappointing. Here, we present a novel approach to directly program myeloid cells by administering novel TROP2 CAR mRNA encapsulated in lipid nanoparticles (LNPs).
View Article and Find Full Text PDFACS Appl Mater Interfaces
December 2024
Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, 1001 Ta-Hseuh Road, Hsinchu 300093, Taiwan.
Three new bithiophene imide (BTI)-based organic small molecules, (), (), and (), with varied alkyl side chains, were developed and employed as self-assembled monolayers (SAMs) applied to NiOx films in tin perovskite solar cells (TPSCs). The NiOx layer has the effect of modifying the hydrophilicity and the surface roughness of ITO for SAM to uniformly deposit on it. The side chains of the SAM molecules play a vital role in the formation of a high-quality perovskite layer in TPSCs.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!