Because little is known about how the innate immune response influences skin pigmentation, we examined whether Toll-like receptor (TLR) agonists participate in melanogenesis and melanosome transportation. We observed that TLR2/2 agonist HKLM and TLR3 agonist Poly(I:C) increased the amount of extracellular melanin from primary human epidermal melanocytes. HKLM, but not Poly(I:C), increased the melanogenic genes such as tyrosinase and dopachrome tautomerase. Poly(I:C) increased the expression of Rab27A, a molecule that facilitates melanosome transport to perimembranous actin filament. UVB irradiation induced Rab27A and melanosome transportation in a similar manner of Poly(I:C). SiRNA for TLR3 or Rab27A suppressed the perimembranous accumulation of Gp100-positive vesicles in melanocytes and decreased melanin transfer to neighboring keratinocytes induced by both Poly(I:C) and UVB. These results suggest that the microenvironment in the epidermis and innate immune stimuli, such as microbiome and ultraviolet represented here by TLR2 and TLR3 agonists, could affect the melanogenesis in human melanocytes.

Download full-text PDF

Source
http://dx.doi.org/10.1111/pcmr.12703DOI Listing

Publication Analysis

Top Keywords

polyic increased
12
melanogenesis melanosome
8
melanosome transport
8
human melanocytes
8
innate immune
8
melanosome transportation
8
polyic
5
toll-like receptors
4
receptors enhance
4
enhance melanogenesis
4

Similar Publications

Article Synopsis
  • Type 1 diabetes (T1D) results from an autoimmune attack that destroys insulin-producing beta cells, with its initiation linked to genetic, immunological, and environmental factors, particularly viral infections like Coxsackievirus B (CVB).
  • Research reveals that CVB serotype 1 (CVB1) may trigger autoimmune responses in genetically susceptible individuals, but the exact mechanisms of its replication in beta cells are unclear.
  • New findings indicate that the N6-methyladenosine (m6A) modification influences CVB1 amplification, where downregulating m6A "writers" increases viral replication, while inhibiting "erasers" like FTO significantly decreases infectious CVB1 production, highlighting m6A's role
View Article and Find Full Text PDF

Maternal immune activation accelerates pup reflex development and alters immune proteins in pup stomach contents and brain.

Brain Res

December 2024

Dalhousie University, Faculty of Science, Department of Psychology and Neuroscience, Halifax, NS, Canada. Electronic address:

Prenatal infection increases the risk for neurodevelopmental disorders including autism spectrum disorder and schizophrenia. To better understand this link, a number of maternal immune activation (MIA) rodent models have been studied. However, the majority of these studies focus on adult behavioural outcomes that mirror adult symptoms related to neurodevelopmental disorders.

View Article and Find Full Text PDF

Stress responses to bacterial and viral mimetics in polycystic ovary syndrome model rats.

Brain Behav Immun Health

July 2024

Department of Obstetrics and Gynecology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan.

Polycystic ovary syndrome (PCOS) is associated with an increased risk of psychological distress as well as enhanced responses to psychosocial stress. Recently, it was hypothesized that PCOS patients may be at high risk of novel COVID-19 infections and worse clinical presentations during such infections. Here, we evaluated the effects of PCOS on stress responses to bacterial and viral mimetics using dihydrotestosterone-induced PCOS model rats.

View Article and Find Full Text PDF

miR-146a and miR-146b regulate the expression of ICAM-1 in giant cell arteritis.

J Autoimmun

April 2024

Unit of Clinical Immunology, Allergy and Advanced Biotechnologies, Azienda Unità Sanitaria Locale-IRCCS di Reggio Emilia, Reggio Emilia, Italy. Electronic address:

Giant cell arteritis (GCA) is an inflammatory disease of large/medium-sized arteries. MiRNAs are small, non-coding RNAs that inhibit gene expression at post-transcriptional level. Several miRNAs have been shown to be dysregulated in temporal artery biopsies (TABs) from GCA patients, but their role is unknown.

View Article and Find Full Text PDF

Background/aim: Retinoic acid-inducible gene (RIG)-I like receptors (RLRs) are expressed on renal proximal tubular epithelial cells (RPTECs) in viral nephropathy, indicating the presence of RLR-mediated innate immune responses in RPTECs. Hypoxia is also known to affect innate immunity. This study investigated the effects of hypoxia, and hypoxia-inducible factor (HIF) on innate immunity in RPTECs.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!