A priori, early exposure to a wide range of bacteria, viruses, and parasites appears to fortify and regulate the immune system, potentially reducing the risk of autoimmune diseases. However, improving hygiene conditions in numerous societies has led to a reduction in these microbial exposures, which, according to certain theories, could contribute to an increase in autoimmune diseases. Indeed, molecular mimicry is a key factor triggering immune system reactions; while it seeks pathogens, it can bind to self-molecules, leading to autoimmune diseases associated with microbial infections. On the other hand, a hygiene-based approach aimed at reducing the load of infectious agents through better personal hygiene can be beneficial for such pathologies. This review sheds light on how the evolution of the innate immune system, following the evolution of molecular patterns associated with microbes, contributes to our protection but may also trigger autoimmune diseases linked to microbes. Furthermore, it addresses how hygiene conditions shield us against autoimmune diseases related to microbes but may lead to autoimmune pathologies not associated with microbes.
The development of natural substances derived from nature poses a significant challenge as technologies for the extraction and characterization of active principles advance. Hispolon has received a lot of attention in recent years, ascribable to its wide range of biological activities. It is a phenolic molecule that was extracted from several mushroom species such as Phellinus igniarius, Phellinus linteus, Phellinus lonicerinus, Phellinus merrillii, and Inonotus hispidus. To provide a comprehensive overview of the pharmacological activities of hispolon, this review highlights its anticancer, anti-inflammatory, antioxidant, antibacterial, and anti-diabetic activities. Several scientific research databases, including Google Scholar, Web of Science, PubMed, SciFinder, SpringerLink, Science Direct, Scopus, and, Wiley Online were used to gather the data on hispolon until May 2024. The in vitro and in vivo studies have revealed that hispolon exhibited significant anticancer properties through modifying several signaling pathways including cell apoptosis, cycle arrest, autophagy, and inhibition of angiogenesis and metastasis. Hispolon's antimicrobial activity was proven against many bacterial, fungal, and viral pathogens, highlighting its potential use as a novel antimicrobial agent. Additionally, hispolon displayed potent anti-inflammatory activity through the suppression of key inflammatory mediators, such as inducible NO synthase (iNOS), tumor necrosis factor-α (TNF-α), and cyclooxygenases-2 (COX-2), and the modulation of mitogen-activated protein kinases (MAPK) and nuclear factor kappa B (NF-κB) signaling pathways. The antioxidant potential of hispolon was attributed to its capacity to neutralize reactive oxygen species (ROS) and to increase the activity of antioxidant enzymes, indicating a possible involvement in the prevention of oxidative stress-related illnesses. Hispolon's antidiabetic activity was associated with the inhibition of aldose reductase and α-glucosidase. Studies on hispolon emphasized its potential use as a promising scaffold for the development of novel therapeutic agents targeting various diseases, including cancer, infectious diseases, inflammatory disorders, and diabetes.