Search Results (181)

Small extracellular vesicles (sEVs) derived from mesenchymal stem cells have emerged as promising therapeutic agents in regenerative dermatology. This study evaluated the safety and efficacy of Bio-Pulsed avian mesenchymal stem cell-derived sEVs (AMSC-sEVs), topically applied for hair follicle stimulation and skin rejuvenation. Two prospective, single-arm clinical trials were conducted: one involving 30 participants using a hair ampoule over 60 days, and the other involving 30 participants applying a facial essence for 28 days. Objective measurements demonstrated significant improvements in the anagen/telogen hair ratio, reduced shedding, increased collagen density, and reduced wrinkle depth and pigmentation. Small RNA sequencing and qPCR profiling confirmed that Bio-Pulsed AMSC-sEVs were enriched with regenerative microRNAs, such as miR-21-5p and miR-199a-5p, associated with anti-inflammatory and anti-aging effects. No adverse events were reported. These findings suggest that Bio-Pulsed AMSC-sEVs may offer a safe, non-invasive, and cell-free approach to enhance skin and hair regeneration in human subjects. Full article

Androgenetic alopecia (AGA), the most prevalent form of hair loss worldwide, faces significant therapeutic challenges due to high costs and limited efficacy of current interventions, necessitating safer and more effective solutions. Periplaneta americana (L.)-derived PA-011, endowed with anti-inflammatory and antioxidant properties, has demonstrated notable hair growth-promoting effects in AGA mouse models. This study employed LC-MS/MS, peptidomics, and network pharmacology to characterize PA-011’s chemical composition and predict its potential targets in AGA pathogenesis. Using Western blot and RT-qPCR, PA-011 intervention significantly inhibited inflammatory responses and oxidative stress levels in mouse skin tissues. Concurrently, PA-011 activated the proliferative potential of hair follicle stem cells, as demonstrated by upregulated expression of the cell proliferation marker Ki67, and activated the Wnt/β-catenin signaling pathway in DHT-induced AGA mice. Transcriptomic and metabolomic analyses revealed multi-target effects of PA-011, including modulation of PI3K-Akt/MAPK pathways, pentose phosphate metabolism, and amino acid biosynthesis. 16S rRNA sequencing and metagenomic analysis showed that AGA disrupts skin microbial homeostasis, while PA-011 intervention normalized the microbiota composition. Topical application of PA-011 promoted robust hair regrowth without detectable toxicity in safety assessments. This preclinical study establishes PA-011 as a promising candidate for AGA therapy, warranting further translational investigation. Full article

Exploring the neurogenic potential of extraneural stem cells under the actions of proneurogenic biomolecules may enhance the success of autologous cell therapy for neurodegenerative diseases such as Parkinson’s. Neural stem and progenitor cells (NSPCs) from extraneural tissues have emerged as potential sources of functional dopaminergic (DA) neurons. Background/Objectives: This study aimed to generate DA neurons from ovarian cortical cells (OCC)-derived NSPCs to elucidate whether follicle-stimulating hormone (FSH) can enhance this process and to evaluate the electrophysiological functionality of differentiated neural cells using the patch-clamp technique. Methods: OCC-NSPCs were differentiated towards the DA pathway during the neurosphere (NS) assay after two culture periods for cell expansion (CEP-1, CEP-2) with one of these media: M1 (positive control with epidermal growth factor, EGF, and fibroblast growth factor2, FGF2), M2 (control), and M3 (M2 with FSH, 50 ng/mL). Image analysis, morphometric evaluation, cell proliferation assays, and gene expression analysis of NSPC-specific transcripts were performed. After CEP-2, NS cells were cultured for 30 days in a serum-free medium containing Sonic-Hedgehog, FGF2, FGF8, and brain-derived neurotrophic factor (BDNF) for differentiation. At the end of culture, expression, and immunolocalization of GFAP, Olig2, NeuN, and tyrosine hydroxylase (TH) were analyzed in cells, along with patch-clamp recordings in differentiated neurons. Results: Cell proliferation and NS development were larger in OCC-NSPCs from groups M1 and M3 than in M2. Expression of NSPC-related transcripts was higher in M2; however, M1 and M3 cultures showed greater expression of differentiation markers NeuN, GFAP, Olig2, and TH. NeuN, GFAP, and TH were immunolocalized in differentiated cells and NS that were generated during differentiation. TH was localized in neural precursor cells, some neurons, core cells of small-, medium-, and large-sized NS, and in cells close to the outer cell layer of large NS, with greatest immunolocalization percentages in NS primed with FSH during CEP-1/2 (M3). Electrophysiological recordings revealed a major incidence of plateau potentials and a significant proportion of complete action potentials, reflecting successful functional neuronal differentiation. Conclusions: DA precursors and functional neurons can be successfully obtained after OCC-NSPCs-directed differentiation. FSH priming during the expansion period enhances the neurogenic potential of these cells towards the DA pathway. Future research will explore the eventual therapeutic use of these findings for neurodegenerative diseases. Full article

The development and replacement of hair play a significant role in the life history of animals. In recent years, retinoic-acid-related orphan receptor alpha (Rorα) has been found to participate in the regulation of hair follicle development, yet the underlying mechanisms remain incompletely understood. This study aims to analyze the regulatory role of Rorα on the cytoskeleton of hair follicle stem cells (HFSCs). We treated HFSCs with a RORA agonist and subsequently analyzed differential gene expression using qPCR, Western blotting, and immunofluorescence, finding that agonist-induced activation of RORA suppressed the expression levels of cytoskeleton-related genes. Additionally, F-actin staining with phalloidin, followed by migration assays and wound healing tests for cell migration detection, revealed that this process affected the cytoskeletal state of HFSCs and inhibited their migration and adhesion capabilities. We further conducted interaction analyses using CUT&RUN combined with ddPCR and EMSA, demonstrating that RORA can bind to the promoter regions of the Actg1 gene and regulate their transcription. This study contributes to a comprehensive understanding of the regulatory processes involved in hair follicle development and may provide broader insights into the treatment of diseases such as alopecia. Full article

Hair follicle stem cells (HFSCs) are pluripotent stem cells located in the bulges of hair follicles. Apoptosis regulates tissue homeostasis by eliminating unnecessary or damaged cells during development and aging. VDAC2, located in the outer mitochondrial membrane (MOM), is a key apoptosis regulator, but its role in cashmere goat hair follicles remains unclear. In previous studies, through proteomic sequencing, we found that VDAC2 was significantly differentially expressed in the anagen, catagen, and telogen phases of the hair follicles of Albas cashmere goats. This study aimed to explore the role of VDAC2 in secondary hair follicle stem cells (SHFSCs) and preliminarily investigate its regulatory mechanism through RNA-seq. Overexpression of VDAC2 promoted apoptosis in SHFSCs, while knockdown had the opposite effect. RNA-seq analysis, together with expression validation of downstream genes, indicates that the P53 signaling pathway may be involved in VDAC2-mediated SHFSC regulation. RT-qPCR and Western blotting confirmed that VDAC2 activated the P53 signaling pathway in SHFSCs. Furthermore, the use of a P53 inhibitor after VDAC2 overexpression partially rescued the apoptosis of cells caused by VDAC2. These results demonstrate that VDAC2 plays an important role in SHFSC apoptosis. Our findings greatly enhance our understanding of the role of VDAC2 in SHFSC apoptosis and hair follicle growth. Full article

With alopecia affecting millions globally, recent advancements in the understanding of hair follicle biology have driven the development of novel therapies focused on hair regrowth. This review discusses two emerging therapeutic strategies: hair follicle neogenesis and the modulation of the Wnt/B-catenin signaling pathway. Hair follicle neogenesis, a frontier once considered impossible to achieve in adult humans, has recently gained traction due to advancements in stem cell biology and further understanding of the epithelial–mesenchymal interactions that are critical to hair follicle development. Such an approach shows significant potential for addressing conditions leading to hair loss, such as androgenetic and scarring alopecias. The Wnt/B-catenin signaling pathway, a critical intracellular pathway responsible for hair follicle cycles, has gained traction as a target for therapeutic interventions. Studies show that stimulating this pathway leads to hair follicle growth, while its inhibition prompts hair follicle regression. Investigations demonstrate clinical efficacy of small molecule inhibitors and peptides, such as PTD-DBM, which activates the Wnt/β-catenin pathway by interfering with CXXC5, a negative regulator that inhibits pathway activation. Such therapies show potential as more effective treatment options than existing solutions such as finasteride and minoxidil. Adjunctive therapies, such as low-level laser therapy, have also shown clinical efficacy, further highlighting how modulation of this pathway stimulates follicular regrowth. While these novel therapies require further research to validate their efficacy and to gain additional insight into their risk profile, it is clear that alopecia treatment is approaching a new frontier beyond traditional pharmacologic interviews, with regenerative medicine and pathway modulation paving the way forward. Full article

Stem cell-derived secretome and exosomes present a promising cell-free strategy for tissue repair and wound healing. This study aimed to isolate and characterize, for the first time, exosomes derived from rat hair follicle stem cells (rHFSCs) and to evaluate their wound-healing potential alongside rHFSC secretome. Exosomes were isolated via ultracentrifugation and characterized using Reverse Transcriptase Polymerase Chain Reaction (RT-PCR), biomarker profiling and protein quantification. Scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS) confirmed their spherical morphology, diameter and elemental composition. Protein quantification showed higher protein content in the secretome than in exosomes. RT-PCR and biomarker profiling highlighted the therapeutic relevance of the exosomal cargo compared to parent rHFSCs. Functional analysis of 30 wound-healing biomolecules validated their pro-regenerative potential. Cytocompatibility was confirmed via the PrestoBlue™ viability assay, while scratch assays demonstrated significant wound closure in the treated groups, both with and without mitomycin C. These findings highlight the potential of rHFSC-derived exosomes and secretome as innovative, cell-free therapeutic agents for cutaneous regeneration. This study advances our understanding of their role in wound healing and underscores their broader applicability in regenerative medicine. Full article

Background: Intraovarian platelet-rich plasma (PRP) has emerged as a novel intervention at the intersection of reproductive medicine and regenerative biology. As women with diminished ovarian reserve (DOR), poor response to stimulation, or premature ovarian insufficiency (POI) seek fertility solutions, PRP provides a scientifically plausible—yet exploratory—strategy to restore or augment ovarian function. The proposed pathways include the stimulation of local stem cells, tissue remodeling, neoangiogenesis, and the potential reawakening of dormant follicles. Methods: This narrative review critically synthesizes the existing literature on intraovarian PRP therapy. It draws from published case series, pilot studies, and preclinical data to evaluate the biological rationale, clinical outcomes, and current limitations of PRP use in women with DOR and POI. Results: Early clinical findings, albeit limited to modest case series and pilot investigations, reveal promising outcomes such as improved ovarian reserve markers, menstrual restoration, and infrequent spontaneous pregnancies in women who had previously been unresponsive to treatment. However, the variability in preparation techniques, patient selection criteria, and outcome measures limits the generalizability of these results. Conclusions: While intraovarian PRP presents an exciting frontier in reproductive medicine, the absence of defined protocols, controlled trials, and long-term safety data underscores its experimental nature. Future research should focus on standardizing methodologies, conducting randomized controlled trials, and elucidating the molecular mechanisms underlying observed clinical effects to establish PRP’s role in managing poor ovarian response and POI. Full article

The Qinling giant panda has a high susceptibility to skin damage, which affects its survival. Although their healing efficacy in panda injuries remains unexplored, extracellular vesicles from adipose-derived mesenchymal stem cells (ADMSC-EVs) have shown promise in regenerative medicine. In this study, ADMSC-EVs were successfully obtained from Qinling giant pandas using ultracentrifugation, and proteomic techniques were used to analyze their composition and function. Primary skin fibroblasts from Qinling giant pandas were isolated and cultured to explore the effects of ADMSC-EVs on cell proliferation and migration. Additionally, a mouse model of skin injury was used to assess their wound healing effects. The ADMSC-EVs contained various substances, particularly proteins, with fifty unique proteins involved in transport, catabolism, and signal transduction identified. The application of ADMSC-EVs in a mouse model accelerated wound healing and promoted the regeneration of the epidermal and dermal layers. It facilitated the repair of skin appendages, including hair follicles and sebaceous glands. Additionally, ADMSC-EVs enhanced collagen deposition, stimulated angiogenesis, and reduced inflammation. Our findings confirm that ADMSC-EVs significantly improve skin healing, thus supporting the theoretical framework for the clinical use of giant panda extracellular vesicles and underscoring their potential for preserving the genetic resources of the Qinling giant panda. Full article

Hair loss disorders pose a substantial global health burden, affecting millions of individuals and significantly impacting quality of life. Despite the widespread use of approved therapeutics like minoxidil and finasteride, their clinical efficacy remains limited. These challenges underscore the pressing need for more targeted and effective therapeutic solutions. This review examines the latest innovations in hair loss drug discovery, with a focus on small-molecule inhibitors, biologics, and stem cell-based therapies. By integrating insights from molecular mechanisms and leveraging advancements in research methods, the development of next-generation therapeutics holds the potential to transform the clinical management of hair loss disorders. Future drug development for hair loss disorders should prioritize antibody therapy and cell-based treatments, as these approaches offer unprecedented opportunities to address the limitations of existing options. Antibody therapies enable precise targeting of key molecular pathways involved in hair follicle regulation, providing highly specific and effective interventions. Similarly, cell-based therapies, including stem cell transplantation and dermal papilla cell regeneration, directly address the regenerative capacity of hair follicles, offering transformative potential for hair restoration. Full article

Background: This paper briefly reviews the most important endocrine features of primary ovarian insufficiency (POI) and shows their relevance for the diagnosis and treatment of this condition. Introduction: Endocrine disturbances in POI cause problems for both the fertility and general health status of the affected women. Both subfertility and infertility result from the depletion of growing ovarian follicles which, in its turn, is the causative factor of hypoestrogenism; this is responsible for most of the general health problems affecting women. Method: Search of literature. Results and conclusion: A combination of high-serum follicle-stimulating hormone (FSH) and low 17β-estradiol (E2) concentrations is a key feature characterizing POI and is the decisive element for POI diagnosis. However, an in-depth search for possible genetic and non-genetic causes is important for adequate counseling regarding prevention and early intervention. The treatment of general health problems, based on correcting hypoestrogenism through hormone replacement therapy (HRT), is relatively easy. On the other hand, resolving infertility is a much more difficult task, and oocyte donation is the only really efficient instrument. Fertility preservation is a suitable alternative in patients with early POI diagnosis, in whom some viable follicles are still present in the ovaries. In patients who refuse oocyte donation, intraovarian injection of autologous platelet-rich plasma and in vitro activation of dormant follicles may be considered. Other innovative treatments, such as stem cell therapies or nuclear transfer, are currently under investigation. Full article

Outer bulge (OB) hair follicle stem cells (HFSCs) play a crucial role in maintaining hair follicle structural stability and regulating the hair follicle cycle. Previous studies demonstrated that keratin 24 (Krt24) exhibits spatiotemporally restricted expression in OB HFSCs. Here, we report the generation of the Krt24-Cre^ERT2 mouse line. When crossed with Rosa26^LSL-tdTomato or Rosa26^LSL-DTR reporter lines, offspring exhibited specific labeling (Krt24-Cre^ERT2;Rosa26^LSL-tdTomato) or ablation (Krt24-Cre^ERT2;Rosa26^LSL-DTR) of Krt24⁺ cells. In Krt24-Cre^ERT2;Rosa26^LSL-tdTomato mice, phase-specific tamoxifen (TAM) administration demonstrated spatiotemporal fidelity of Cre activity to endogenous Krt24 expression patterns. Lineage tracing revealed that tdTomato-labeled Krt24⁺ cells differentiated into the outer root sheath (ORS) during the anagen phase and persisted when hair follicles reentered telogen. Ablation of Krt24⁺ cells via diphtheria toxin (DT) administration significantly delayed anagen initiation. Mice under continuous depletion of Krt24⁺ HFSCs experienced substantial mortality after ionizing irradiation. Notably, ionizing radiation triggered a marked expansion of tdTomato-labeled Krt24⁺ cells, accompanied by maintained hair follicle homeostasis. Taken together, this study established a Krt24-Cre^ERT2 mouse line targeting OB HFSCs, which are essential for hair follicle development and damage repair. Full article

How to elicit and harness regeneration is a major issue in wound healing. Skin injury in most amniotes leads to repair rather than regeneration, except in hair and feathers. Feather follicles are unique organs that undergo physiological cyclic renewal, supported by a dynamic stem cell niche. During normal feather cycling, growth-phase proximal follicle collar bulge stem cells adopt a ring configuration. At the resting and initiation phases, these stem cells descend to the dermal papilla to form papillary ectoderm and ascend to the proximal follicle in a new growth phase. Plucking resting-phase feathers accelerates papillary ectoderm cell activation. Plucking growth-phase feathers depletes collar bulge stem cells; however, a blastema reforms the collar bulge stem cells, expressing KRT15, LGR6, Sox9, integrin-α6, and tenascin C. Removing the follicle base and dermal papilla prevents feather regeneration. Yet, transplanting an exogenous dermal papilla to the follicle base can induce re-epithelialization from the lower follicle sheath, followed by feather regeneration. Thus, there is a stepwise regenerative strategy using stem cells located in the collar bulge, papillary ectoderm, and de-differentiated lower follicle sheath to generate new feathers after different levels of injuries. This adaptable regenerative mechanism is based on the hierarchy of stem cell regenerative capacity and underscores the remarkable resilience of feather follicle regenerative abilities. Full article

Spermatogenesis is a process of self-renewal of spermatogonial stem cells and their proliferation and differentiation to generate mature sperm. This process involves interactions between testicular somatic (mainly Sertoli cells) and spermatogonial cells at their different stages of development. The functionality of Sertoli cells is regulated by hormones and testicular autocrine/paracrine factors. In this study, we investigated the effects of follicle-stimulating hormone (FSH) and testosterone addition on Sertoli cell cultures that undergo hypotonic shock, with a primary focus on Sertoli cell activity. Cells were enzymatically isolated from testicular seminiferous tubules of 7-day-old mice. These cells were cultured in vitro for 3 days. Thereafter, some cultures were treated with hypotonic shock to remove germ cells. After overnight, fresh media without (control; CT) or with FSH, testosterone (Tes), or FSH+T were added to the hypotonic shock-treated or untreated (CT) cultures for 24 h. The morphology of the cultures and the presence of Sertoli cells and germ cells were examined. The expression of growth factors (CSF-1, LIF, SCF, GDNF) or other specific Sertoli cell factors [transferrin, inhibin b, androgen receptor (AR), androgen binding protein (ABP), FSH receptor (FSHR)] was examined by qPCR. Our immunofluorescence staining showed depletion/major reduction in VASA-positive germ cells in Sertoli cell cultures following hypotonic shock (HYP) treatment compared to untreated cultures (WO). Furthermore, the expression of the examined growth factors and other factors was significantly increased in HYP cultures compared to WO (in the CT). However, the addition of hormones significantly decreased the expression levels of the growth factors in HYP cultures compared to WO cultures under the same treatment. In addition, the expression of all other examined Sertoli cell factors significantly changed following HYP treatment compared to WO and following treatment with FSH and or T. However, the expression levels of some factors remained normal following the treatment of Sertoli cell cultures with one or both hormones (transferrin, Fsh-r, Abp, Ar). Thus, our results demonstrate the crucial role of germ cells in the functionality of Sertoli cells and the possible role of FSH and T in maintaining, at least partially, the normal activity of Sertoli cells following germ cell depletion in vitro by hypotonic shock treatment. Full article

Abnormalities in epidermal keratinocyte proliferation are a characteristic feature of a range of dermatological conditions. These include hyperproliferative states in psoriasis and dermatitis as well as hypoproliferative states in chronic wounds. This emphasises the importance of investigating the proliferation kinetics under conditions of healthy skin and identifying the key regulators of epidermal homeostasis, maintenance, and recovery following wound healing. Animal models contribute to our understanding of human epidermal self-renewal. Human skin xenografting overcomes the ethical limitations of studying human skin during regeneration. The application of this approach has allowed for the identification of a single population of stem cells and both slowly and rapidly cycling progenitors within the epidermal basal layer and the mapping of their location in relation to rete ridges and hair follicles. Furthermore, we have traced the dynamics of the proliferation pattern reorganization that occurs during epidermal regeneration, underlining the role of YAP activity in epidermal relief formation. Full article