The microbiota–gut–brain axis (MGBA) comprises a complex bidirectional communication network integrating neural, immune, metabolic, and endocrine pathways. Dopamine, traditionally viewed as a central neurotransmitter, also plays essential roles in the gastrointestinal (GI) tract, where it regulates motility, secretion, barrier homeostasis, and mucosal immunity. Growing evidence indicates that the gut microbiota significantly contributes to intestinal dopamine metabolism through specialized enzymatic pathways, particularly tyrosine decarboxylase in Enterococcus species and catechol dehydroxylase in Eggerthella species. These microbial reactions compete with host processes, alter dopaminergic tone, and degrade orally administered levodopa (L-DOPA), providing a mechanistic explanation for the variability in treatment response in Parkinson’s disease (PD). Beyond PD, microbially mediated alterations in dopaminergic signaling have been implicated in mood disorders, neurodevelopmental conditions, metabolic dysfunction, and immune-mediated diseases. This review synthesizes current mechanistic and translational evidence on the dopamine–microbiota interface, outlines microbial pathways shaping dopaminergic activity, and highlights therapeutic opportunities including microbiota modulation, dietary strategies, fecal microbiota transplantation, and targeted inhibitors of microbial dopamine metabolism. Understanding this interface offers a foundation for developing personalized approaches in neurogastroenterology and neuromodulatory therapies.
At the level of skin wounds, an electrical potential difference develops between the edges of the wound and the center of the wound, which favors the migration of cells in the process of their healing. Cells migrate in an electric field because they have a certain electrical membrane potential. This potential is due to differences in the transmembrane electrochemical gradient. The transmembrane electrochemical gradient is due to the migration of sodium, potassium, and calcium ions into the corresponding ion channels. If this is the case, the modification of the functionality of these ion channels should influence the membrane potential and, as a consequence, the wound healing process. In this experiment, we set out to investigate whether the chemical manipulation of ion channels by amiodarone influences the wound healing process. Amiodarone blocks several types of ion channels, but at different concentrations: at low concentrations, it blocks only potassium channels; at medium concentrations, potassium and calcium channels; and at high concentrations, it blocks potassium, calcium, and sodium channels. We worked on rats that were given experimental skin lesions and evaluated the influence of the healing of these lesions upon the topical administration of amiodarone in three concentrations, 200 nM, 2000 nM and 200,000 nM, compared to an untreated group and a group treated with benzyl alcohol, the amiodarone solvent. In our experimental conditions, low concentration amiodarone promoted wound healing both in terms of duration of healing and also in terms of speed of healing. This means that blocking some ions, possibly potassium channels, might promote wound healing.
Wound healing involves physical, chemical and immunological processes. Transient receptor potential (TRP) and other ion channels are implicated in epidermal re-epithelization. Ion movement across ion channels can induce transmembrane potential that leads to transepithelial potential (TEP) changes. TEP is present in epidermis surrounding the lesion decreases and induces an endogenous direct current generating an epithelial electric field (EF) that could be implicated in wound re-epithelialization. TRP channels are involved in the activation of immune cells during mainly the inflammatory phase of wound healing. The aim of the study was to review the mechanisms of ion channel involvement in wound healing in in vivo experiments in murine (mice, rats) and how can this process be influenced. This review used the latest results published in scientific journals over the last year and this year to date (1 January 2023–31 December 3000) in order to include the in-press articles. Some types of TRP channels, such as TRPV1, TRPV3 and TRPA1, are expressed in immune cells and can be activated by inflammatory mediators. The most beneficial effects in wound healing are produced using agonists of TRPV1, TRPV4 and TRPA1 channels or by inhibiting with antagonists, antisense oligonucleotides or knocking down TRPV3 and TRPM8 channels.
Paracetamol can induce hypothermia in humans and rodents. The study’s aim is to review the mechanisms of paracetamol-induced hypothermia in rodents or the results issued from in vitro studies on the same species’ tissues (in doses that do not produce hepatic impairment) using the latest developments published in scientific journals over the last 15 years. Available human studies are also analysed. An extensive search in PubMed databases exploring the hypothermic response to paracetamol was conducted. 4669 articles about paracetamol’s effects on body temperature in mice or rats were found. After applying additional filters, 20 articles were selected for review, with 9 of them presented in tabular forms. The analysis of these articles found that the hypothermic effect of paracetamol is due to the inhibition of a cyclooxygenase-1 variant, is potentiated by endothelin receptor antagonists, and can be mediated through GABAA receptors and possibly through transient receptor potential cation channel subfamily A member 1 via N-acetyl-p-benzoquinone imine in the central nervous system. Human studies confirm the in vivo and in vitro experiments in rodents regarding the presence of a hypothermic effect after high, non-toxic doses of paracetamol. Further research is required to understand the mechanisms behind paracetamol’s hypothermic effect in humans.
Non-steroidal anti-inflammatory drugs (NSAIDs) showed effects in some hyperproliferative dermatologic pathologies. The aim of the study is the assessment of anti-psoriasis effect of diclofenac and celecoxib using a mice tail model. The topical application of substances on the proximal mice tails was performed for two weeks. The effects on the epidermal granular layer and mean epidermal thickness (excluding the stratum corneum) were evaluated using hematoxylin–eosin staining. Orthokeratosis degree and percentual drug activity were calculated. A positive control group treated with tretinoin and two negative controls (white soft paraffin and untreated mice) were used. Orthokeratosis degree significantly increased in all the NSAIDs groups (celecoxib 1%, 2% and diclofenac 1%, 2%) and in the tretinoin 0.05% group, versus negative controls. Celecoxib 1% and 2%, tretinoin 0.05% and white soft paraffin significantly increased mean epidermal thickness, versus untreated mice. The values obtained in the case of celecoxib 2% ointment regarding the orthokeratosis degree and percentual drug activity are providing premises for further investigations regarding this effect and the mechanisms of action involved. Celecoxib 2% had the greatest percentual drug activity and is a promising substance for the anti-psoriasis topical treatment. Along with the COX-2 inhibition, celecoxib might have an anti-psoriasis effect by other independent mechanisms.
Wound healing involves physical, chemical and immunological processes. Transient receptor potential (TRP) and other ion channels are implicated in epidermal re-epithelization. Ion movement across ion channels can induce transmembrane potential that leads to transepithelial potential (TEP) changes. TEP present in epidermis surrounding the lesion decreases and induces an endogenous direct current generating an epithelial electric field (EF) that could be implicated in wound re-epithelialization. TRP channels are involved in the activation of immune cells during the inflammatory phase of wound healing. The aim of the study was to review the mechanisms of ion channel involvement in wound healing in in vivo experiments in rodents (mice, rats, rabbits) and how can this process be influenced. This review used the latest results published in scientific journals over the last year and this year to date (1 January 2023–31 December 3000) in order to include the in-press articles. Some types of TRP channels, such as TRPV1, TRPV3, and TRPA1, are expressed in immune cells and can be activated by inflammatory mediators. The most beneficial effects in wound healing are produced using agonists of TRPV1, TRPV4 and TRPA1 channels or by inhibiting with antagonists, antisense oligonucleotides or knocking down TRPV3 and TRPM8 channels.