Influence of Guanine-Based Purines on the Oxidoreductive Reactions Involved in Normal or Altered Brain Functions.

The production of reactive oxygen species (ROS) in the brain is homeostatically controlled and contributes to normal neural functions. Inefficiency of control mechanisms in brain aging or pathological conditions leads to ROS overproduction with oxidative neural cell damage and degeneration. Among the compounds showing therapeutic potential against neuro-dysfunctions induced by oxidative stress are the guanine-based purines (GBPs), of which the most characterized are the nucleoside guanosine (GUO) and the nucleobase guanine (GUA), which act differently.

Guanine inhibits the growth of human glioma and melanoma cell lines by interacting with GPR23.

Guanine-based purines (GBPs) exert numerous biological effects at the central nervous system through putative membrane receptors, the existence of which is still elusive. To shed light on this question, we screened orphan and poorly characterized G protein-coupled receptors (GPRs), selecting those that showed a high purinoreceptor similarity and were expressed in glioma cells, where GBPs exerted a powerful antiproliferative effect. Of the GPRs chosen, only the silencing of GPR23, also known as lysophosphatidic acid (LPA) 4 receptor, counteracted GBP-induced growth inhibition in U87 cells.

Purinergic Signaling in Oral Tissues.

The role of the purinergic signal has been extensively investigated in many tissues and related organs, including the central and peripheral nervous systems as well as the gastrointestinal, cardiovascular, respiratory, renal, and immune systems. Less attention has been paid to the influence of purines in the oral cavity, which is the first part of the digestive apparatus and also acts as the body's first antimicrobial barrier. In this review, evidence is provided of the presence and possible physiological role of the purinergic system in the different structures forming the oral cavity including teeth, tongue, hard palate, and soft palate with their annexes such as taste buds, salivary glands, and nervous fibers innervating the oral structures.

Adipose Stromal/Stem Cell-Derived Extracellular Vesicles: Potential Next-Generation Anti-Obesity Agents.

Over the last decade, several compounds have been identified for the treatment of obesity. However, due to the complexity of the disease, many pharmacological interventions have raised concerns about their efficacy and safety. Therefore, it is important to discover new factors involved in the induction/progression of obesity.