Sensory Neurons in Human Skin Play Key Role in Pigmentation


News Release, Skin Ageing & challenges – 26 September 2022.

Our skin forms the physical boundary between us and the outside world, yet it still holds a surprising number of secrets. Now, researchers from Japan have discovered that sensory nerve cells in our skin do more than just help us feel our way around.

In a study published this month in Cell Reports, a research group led by the Institute of Industrial Science, The University of Tokyo, has revealed that sensory neurons in human skin play an important role in pigmentation.

Pigmentation in our skin is caused in part by a group of substances known as melanin, which are produced by skin cells called melanocytes. When melanocytes are damaged or reduced in number, this leads to either increased or limited melanin production, resulting in pigmentation disorders. Typically, these melanin changes are long term, localized, and uneven – such as skin color patches. The mechanisms that underpin the maintenance and development of these patches are mostly unknown.

“Increasingly, evidence has been pointing to the possibility that the interaction between neurons and melanocytes plays a number of key roles in human skin,” says lead author of the study, Siu Yu Chow. “This includes the regulation of melanocytes by sensory neurons.”

In their study, the researchers explored the relationship between sensory neurons and melanocytes, and found that there was a greater degree of contact between them in skin color patch tissue than control tissue. When cultured with neurons, melanocytes were also found to have higher pigmentation and an increased survival rate. Melanocytes cultured in growth media that had been conditioned with sensory neurons showed increased survival, as well as longer dendrites (branch-like extensions of the cell); these effects were specific to melanocytes.

“Additionally, we identified proteins secreted by sensory neurons, including Repulsive Guidance Molecule B (RGMB),” explains Yoshiho Ikeuchi, senior author. “We discovered that melanocyte survival and darkness is promoted by RGMB.”

The study revealed that sensory neurons play a role in modulating a number of features of human melanocytes via the secretion of RGMB, which is a key factor that stimulates melanocytes.

“Our results highlight how important sensory neurons are to skin pigmentation and physiology,” says Chow.

Pigmentation disorders, including skin color patches, are common and can result in psychosocial problems; they are also often linked with health issues such as neurocutaneous diseases (diseases that affect the nervous system and skin) and melanoma. However, the effectiveness of chemical and topical treatments for these are limited. The results of this study could lead to the development of new drugs for use with current therapies by enabling the discovery of previously unknown molecules and mechanisms that include RGMB.

News source.

Article DOI.

© Photo Copyright : Institute of Industrial Science, The University of Tokyo.

Skin Ageing & Challenges 2022
November 17-18, 2022 – Lisbon, Portugal

Skin Ageing

Skin Microbiome Profile of Healthy Cameroonians and Japanese


The commensal microbes of the skin have a significant impact on dermal physiology and pathophysiology. Racial and geographical differences in the skin microbiome are suggested and may play a role in the sensitivity to dermatological disorders, including infectious diseases.

Little is known about the skin microbiome profiles of people living in Central Africa, where severe tropical infectious diseases impose a burden on the inhabitants. This study provided the skin profiles of healthy Cameroonians in different body sites and compared them to healthy Japanese participants.

The skin microbiome of Cameroonians was distinguishable from that of Japanese in all skin sites examined in this study. For example, Micrococcus was predominantly found in skin samples of Cameroonians but mostly absent in Japanese skin samples. Instead, the relative abundance of Cutibacterium species was significantly higher in healthy Japanese.

Principal coordinate analysis of beta diversity showed that the skin microbiome of Cameroonians formed different clusters from Japanese, suggesting a substantial difference in the microbiome profiles between participants of both countries. In addition, the alpha diversity in skin microbes was higher in Cameroonians than Japanese participants.

These data may offer insights into the determinant factors responsible for the distinctness of the skin microbiome of people living in Central Africa and Asia.

Full Article.

© Photo Copyright: Ogai et al. 2022

Join Dr. Kazuhiro Ogai in Skin Ageing & Challenges 2022 this November to know more about this study.

Submit a related abstract. 

Skin Ageing & Challenges 2022
November 17-18, 2022 – Lisbon, Portugal

In-cytoplasm Mitochondrial Transplantation for Stem Cells Engineering & Tissue Regeneration

Representative images of the wound area (left) and the corresponding fractions of wounds healed (right) by different treatments.

News Release, Skin Aging & Challenges – August 31, 2022

Stem cell therapies are unsatisfactory due to poor cell survival and engraftment. Stem cells used for therapy must be properly “tuned” for a harsh in vivo environment.

Ouyang et al. reported that the transfer of exogenous mitochondria (mito) to adipose-derived mesenchymal stem cells (ADSCs) can effectively boost their energy levels, enabling efficient cell engraftment. The entire process of exogenous mitochondrial endocytosis was captured by high-content live-cell imaging.

Mitochondrial transfer lead to acutely enhanced bioenergetics, with nearly 17% of higher adenosine 5′-triphosphate (ATP) levels in ADSCs treated with high mitochondrial dosage and further resulted in altered secretome profiles of ADSCs.  It also induced the expression of 334 mRNAs in ADSCs, which are mainly linked to signaling pathways associated with DNA replication and cell division.

They hypothesize that increase in ATP and cyclin-dependent kinase 1 and 2 expression might be responsible for promoting enhanced proliferation, migration, and differentiation of ADSCs in vitro. More importantly, mito-transferred ADSCs display prolonged cell survival, engraftment and horizontal transfer of exogenous mitochondria to surrounding cells in a full-thickness skin defect rat model with improved skin repair compared with nontreated ADSCs.

These results demonstrate that intracellular mitochondrial transplantation is a promising strategy to engineer stem cells for tissue regeneration.

Article DOI.

© Photo Copyright: Ouyang et al.

Join Dr. Ouyang in Skin Ageing & Challenges 2022 this November to know more about the in-cytoplasm mitochondrial transplantation procedure.

Submit a related abstract. 

Skin Ageing & Challenges 2022
November 17-18, 2022 – Lisbon, Portugal

The University of Lisbon, Faculty of Pharmacy, Lisboa, Portugal will host the 13th Annual Meeting on Skin Challenges 2022 this November

Skin challenges 2022The 13th Annual Meeting on Skin Ageing & Challenges 2022 will take place on November 17-18 at the University of Lisbon, Faculty of Pharmacy, Lisboa, Portugal and Online. This meeting is endorsed by International Society of Microbiota (ISM), and headed by Prof. Jean Krutmann, IUF – Leibniz Research Institute for Environmental Medicine, Leibniz, Germany.

Among the topics that will be presented during the meeting:

  • Skin Ageing & Challenges – State of the Art
  • Skin Microbiota – Recent Scientific Advances
  • Skin Regeneration & Wound Healing
  • Extracellular Vesicles & Skin: The Points of View
  • Lifestyle, Diet and Skin Ageing: The Inside Beauty
  • Artificial Intelligence & Skin: Advances & Perspective
  • Skin Challenges 2022 Innovations

Artificial Intelligence & Skin: Advances & Perspective

Skin Ageing & Challenges 2022 will introduce a new session on Artificial Intelligence & Skin. The aim of this session is to present the last advances and innovations in the field of Artificial Intelligence (AI) applied to Skin and skincare, and to connect all the key actors involved in skin assessment, analysis and algorithm: clinician, dermatologist, academic, start-up, industrial, mathematician, computer scientists, and bioinformatician, in order to initiate the discussions on the development and applications of novel AI technologies to skincare.

In this session, a representative from PerfectCorp, USA, will elaborate this topic and underline how artificial intelligence can be incorporated in the dermatology industry.

Oliver Schmidt, Chemnitz University of Technology, Germany, will also join the session to introduce a new concept of Electronic Skin that Anticipates and Perceives Touch from Different Directions.

More about the speakers and topics

Call for Innovations

The scientific committee invites all academics and industrials to present their recent innovations and research in the Artificial Intelligence field.

About the venue:

The Faculty of Pharmacy – University of Lisbon, Portugal, will welcome the 13th Annual Meeting on Skin Ageing & Challenges. More about the venue.

Extracellular Vesicles & Skin: The Points of View

Skin Ageing & Challenges 2022 will dedicate a new session to “Extracellular Vesicles & Skin: The Points of View”. In this session, international experts in the field will present their latest research, and introduce the most recent advances and discoveries incorporating extracellular vesicles and exosomes in skin care.

Professional researchers will present their perspectives on Extracellular Vesicles as theranostic tools for skin diseases, ageing, and injuries:

Extracellular Vesicles: Potential Theranostic Platforms for Skin Diseases and Aging
Sun Hwa Kim, Korea Institute of Science and Technology, Korea  

Extracellular Vesicle Therapy for Skin Injuries 
Piul S. Rabbani, New York University School of Medicine, USA

Further, outlooks on the use of extracellular vesicles for skin will be discussed by specialists:

Exosome Technology: Pearls & Pitfalls for Skin Rejuvenation
Saranya Wyles, Mayo Clinic Department of Dermatology, USA

Extracellular Vesicles in Facial Aesthetics
Jia Xian Law, Universiti Kebangsaan Malaysia 

Skin Ageing & Challenges 2022
November 17-18, 2022 – Lisbon, Portugal

Submit your Best Image for the Contest

Skin Ageing & Challenges 2022 invites you to submit your best skin image for a chance to win.

All microscopic and macroscopic images showing the in vivo & ex vivo skin cells and the effects of lifestyle, environment, and microbiota on skin and skin aging, will be accepted. The images related to regeneration and wound healing process will also be welcomed. 

Submit a memorable image you’ve taken this past year and enter the draw to win a free registration for next year’s meeting. Entries must be original and contestants should be registered to the Skin Ageing & Challenges 2022 Congress. Results will be announced during the 15th Annual meeting this November. 

Entries must be original. We also accept all the artwork and drawings.

By submitting your image and caption, you give the ISM and ISANH permission to communicate your image (with proper credit being given).

Image Submission Guidelines

To submit, please send us in one page:

  1. Your name
  2. Your complete affiliation
  3. A picture of you (optional)
  4. Your Skin Image with:
  • The description of the image
  • The context of the study

And send it to skin(at) 


Skin Ageing & Challenges  2022
November 16-18, 2022 – Lisbon, Portugal

Mitochondria-Targeted Hydrogen Sulfide Delivery Molecules Against Photoaging

News Release, Skin Aging & Challenges – August 8, 2022

Oxidative stress and mitochondrial dysfunction play a role in the process of skin photoaging via activation of matrix metalloproteases (MMPs) and the subsequent degradation of collagen. The activation of nuclear factor E2-related factor 2 (Nrf2), a transcription factor controlling antioxidant and cytoprotective defense systems, might offer a pharmacological approach to prevent skin photoaging.

Dr. Panich et al. investigated a pharmacological approach to prevent skin photoaging, and also investigated a protective effect of the novel mitochondria-targeted hydrogen sulfide (H2S) delivery molecules AP39 and AP123, and nontargeted control molecules, on ultraviolet A light (UVA)-induced photoaging in normal human dermal fibroblasts (NHDFs) in vitro and the skin of BALB/c mice in vivo.

They reported:

In NHDFs, AP39 and AP123 (50–200 nM) but not nontargeted controls suppressed UVA (8 J/cm2)-mediated cytotoxicity and induction of MMP-1 activity, preserved cellular bioenergetics, and increased the expression of collagen and nuclear levels of Nrf2.

In in vivo experiments, topical application of AP39 or AP123 (0.3–1 μM/cm2; but not nontargeted control molecules) to mouse skin before UVA (60 J/cm2) irradiation prevented skin thickening, MMP induction, collagen loss of oxidative stress markers 8-hydroxy-2′-deoxyguanosine (8-OHdG), increased Nrf2-dependent signaling, as well as increased manganese superoxide dismutase levels and levels of the mitochondrial biogenesis marker peroxisome proliferator-activated receptor-gamma coactivator (PGC-1α).

 Thus targeting H2S delivery to mitochondria may represent a novel approach for the prevention and treatment of skin photoaging, as well as being useful tools for determining the role of mitochondrial H2S in skin disorders and aging. 

© Photo CopyrightRead the full review.

Dr. Panich will be discussing the results of this brilliant study during Skin Ageing & Challenges 2022 Congress. Reserve your spot.

Skin Ageing & Challenges 2022
November 17-18, 2022 – Lisbon, Portugal

Overview on Skin Ageing & Challenges 2022

The 13th Annual Meeting on Skin Ageing & Challenges 2022 will take place from November 16th to the 18th at The University of Lisbon, Faculty of Pharmacy, Lisboa, Portugal and Online. More than 300 participants will be attending in person and online after a long period of online meetings.

This year’s conference will answer all your questions concerning healthy skin. International experts will gather to present their latest discoveries in the field. Skin Ageing & Challenges 2022 speakers will shed light on the following topics: Skin microbiome and mycobiome, skin cancer, atopic skin inflammation, wound healing, engineered stem cells and silk biomaterials, exosome technology, mitochondrial transplantation, skin ageing, skin rejuvenation, senolytic flavonoids, skin photo-protection, facial aesthetics, diet and skin, artificial intelligence, electronic skin

Meet the Speakers.

Abstract Submission

  • Short Oral Presentation submission deadline: October 26
  • Poster Presentation submission deadline: October 31

More details on abstract submission


You can register for in-person or online participation. Registration details

Early bird registration deadline: September 30.

Please contact us for any further information.

Best Image Winner 2020

Among the Best Images contest submitted images, the organizing committee selected Dr. Lia Mara Grosso Neves’s submission.

Dr. Neves also will present a short oral entitled “Polysaccharide‐rich hydrogel formulation combined with photobiomodulation repairs UV‐induced photodamage in mice skin” during the Skin Challenges 2020 Virtual Congress.

Summary of talk: The development of new therapies for the treatment of photoaging has gained importance in the last decades. In this scenario, natural products represent interesting tools for the prevention and treatment of skin aging. The therapy called photobiomodulation (PBM) refers to the use of photons, in a non-thermal irradiance, to alter the biological activity of cells and tissues. Non-ablative lasers have been increasingly used in the aesthetic treatment of fine wrinkles and skin photoaging. Will be demonstrated the biomodulatory effects of a polysaccharide-rich hydrogel formulation extracted from Lycium barbarum fruits combined with PBM repairing the UVR-induced photodamage on the skin of hairless mice.