Plant-Based Nano-Delivery Systems in the Treatment of Inflammatory Disorders

Inflammation is strongly related to the development of multiple chronic diseases, such as cardiovascular and autoimmune diseases, and is considered a crucial target for new therapeutic approaches, since it significantly impacts public health, contributes to high mortality rates, and decreases the quality of life. Conventional anti-inflammatory approaches are commonly used, but they present multiple limitations, such as undesirable side effects and low target-specificity. Medicinal plants and their bioactive phytochemical compounds have been studied in recent years and are considered promising alternatives to classical therapies. They are widely recognized for their capacity to modulate inflammatory pathways, regulate inflammatory responses, and consequently reduce inflammation and related symptoms. Although they are considered a good therapeutic alternative, their application in the human body is limited by certain characteristics, such as low solubility, which leads to rapid metabolism and excretion by the organism, significantly reducing bioavailability; for these reasons, the use of medicinal plants remains a biopharmaceutical challenge. Nanotechnology represents a promising tool in this context, since it can improve several characteristics of these compounds. By incorporating plant-derived compounds in nanosystems, considerable advantages, including sustained release, protection from degradation, an increase in the specificity to target tissues, and consequent reduction in toxicity, can be achieved. Thus, nanosystems promote more favorable therapeutic outcomes. This work aims to compile scientific evidence supporting the use of medicinal plants and their bioactive phytochemical compounds, incorporated in nanosystems, in inflammatory disorders. This review enlarges knowledge by integrating both in vitro and in vivo studies involving multiple medicinal plants and bioactive phytochemical compounds, describing their mechanisms of action and the nanosystems employed for drug delivery. In the future, the need for deeper mechanistic studies, the development of targeted and stimuli-responsive systems, and advancement toward clinically translatable, sustainable, and cost-effective plant-based nanotherapies is required.