The antioxidant activity of four species of the Malvaceae family (Sidastrum micranthum (A. St.-Hil.) Fryxell, Wissadula periplocifolia (L.) C. Presl, Sida rhombifolia (L.) E. H. L and Herissantia crispa L. (Brizicky)) were studied using the total phenolic content, DPPH radical scavenging activity and Trolox equivalent antioxidant capacity (TEAC) assays. The antioxidant activity of the crude extract, phases and two isolated flavonoids, kaempferol 3,7-di-O-α-l-rhamnopyranoside (lespedin) and kaempferol 3-O-β-d-(6''-E-p-coumaroil) glucopyranoside (tiliroside) was determined. The results showed that there is a strong correlation between total polyphenol contents and antioxidant activity of the crude extract of Sidastrum micranthum and Wissadula periplocifolia; however, this was not observed between Sida rhombifolia and Herissantia crispa. The ethyl acetate (EaF) phase showed the best antioxidant effect in the total phenolics, DPPH and TEAC assays, followed by the chloroform (CfF) phase, in most species tested. Lespedin, isolated from the EaF phase of W. periplocifolia and H. crispa may not be responsible for the antioxidant activity due to its low antioxidant activity (IC₅₀: DPPH: 1,019.92 ± 68.99 mg/mL; TEAC: 52.70 ± 0.47 mg/mL); whereas tiliroside, isolated from W. periplocifolia, H. crispa and S. micrantum presented a low IC₅₀ value (1.63 ± 0.86 mg/mL) compared to ascorbic acid in the TEAC assay.

Major depressive disorder (MDD) is a highly prevalent psychiatric condition characterized by complex neurobiological mechanisms, including oxidative stress and neuroinflammation, with microglial activation playing a key role in its pathophysiology. Conventional antidepressants, though widely used, often fail to achieve remission due to limited efficacy, adverse effects, and poor patient adherence. In this context, nanotechnology-based drug delivery systems have emerged as promising strategies to overcome pharmacological limitations, enhance blood–brain barrier (BBB) penetration, and target neuroinflammatory pathways. This narrative review explores the role of microglia as both mediators of neuroinflammation and potential therapeutic targets in MDD. We examine different nanocarriers and their ability to modulate microglial activation, promote a shift from a pro-inflammatory (M1) to an anti-inflammatory (M2) phenotype, and enhance antidepressant efficacy. Preclinical studies have demonstrated that nanoparticle-based systems not only improve drug bioavailability and brain targeting but also potentiate neuroprotective effects by reducing oxidative stress, promoting neurogenesis, and restoring synaptic plasticity. These findings highlight the potential of nanotechnology as a novel approach to precision neuropsychopharmacology. This review aims to provide an integrative perspective on how nanocarrier-based strategies targeting microglia could redefine future therapeutic paradigms for MDD.

Epilepsy is a chronic neurological disorder prevalent worldwide, characterized by recurrent episodes of epileptic seizures. The primary current treatment approach is pharmacological, aimed at reducing the intensity and frequency of seizures, though it does not provide a cure. Neuroinflammation plays a central role in epilepsy by activating glial cells and stimulating the release of inflammatory mediators, further disrupting the balance between excitation and inhibition, thereby promoting the onset and recurrence of seizures. Furthermore, persistent inflammatory processes induce synaptic remodeling and the formation of dysfunctional neural circuits, establishing a pathological cycle in which inflammation and epileptic activity feed into each other. In this regard, natural products represent an important avenue for the discovery of new treatments. Thus, this review aimed to relate the role of the main inflammatory targets (Inflammasome/NLRP3, NF-κB, MAPK, mTOR, COX-2/PGE2, and TLR4/HMGB1) to epilepsy and to investigate in the literature natural products acting through these pathways in the treatment of epileptic seizures. Consequently, inflammatory pathways have emerged as critical targets in epilepsy, highlighting the importance of strategies capable of modulating neuroinflammatory processes. In this context, natural products stand out as promising therapeutic alternatives, given their multitarget mechanisms of action, potential to attenuate neuroinflammation and neuronal hyperexcitability.

Depression is increasingly recognized as a multifactorial disorder involving immune, metabolic, and neurobiological disturbances that extend beyond classical monoaminergic hypotheses. Among xenobiotic-based experimental approaches, lipopolysaccharide (LPS) has become a valuable tool for investigating how peripheral inflammatory stimuli are translated into central neurobiological dysfunction. This narrative review aimed to integrate current evidence regarding the mechanisms by which LPS-induced neuroimmune activation contributes to depression-related phenotypes and to discuss the translational relevance of these findings. Literature searches were performed in PubMed, ScienceDirect, and Google Scholar, focusing on studies addressing inflammatory signaling, oxidative imbalance, inflammasome activation, neurotransmitter dysfunction, and experimental modeling strategies. Current evidence suggests that LPS-induced neuroinflammation involves a dynamic interaction between peripheral immune signaling, mitochondrial dysfunction, redox imbalance, and glial activation, establishing self-amplifying mechanisms capable of sustaining chronic inflammatory states. Such alterations profoundly affect kynurenine metabolism, glutamatergic homeostasis, and reward-related neurotransmission, thereby contributing to synaptic dysfunction and behavioral impairment. Experimental findings obtained from animal, cellular, and computational platforms further support the emergence of integrated therapeutic strategies targeting multiple neuroimmune pathways. Collectively, these observations reinforce the concept that neuroinflammation represents a central biological interface linking xenobiotic exposure to depressive-like behavior.

Major Depressive Disorder (MDD) is a highly prevalent psychiatric condition characterized by complex neurobiological mechanisms, including oxidative stress and neuroinflammation, with microglial activation playing a key role in its pathophysiology. Conventional antidepressants, though widely used, often fail to achieve remission due to limited efficacy, adverse effects, and poor patient adherence. In this context, nanotechnology-based drug delivery systems have emerged as promising strategies to overcome pharmacological limitations, enhance blood–brain barrier penetration, and target neuroinflammatory pathways. This narrative review explores the role of microglia as both mediators of neuroinflammation and potential therapeutic targets in MDD. We examine different nanocarriers — such as polymeric nanoparticles, solid lipid nanoparticles, nanostructured lipid carriers, dendrimers, magnetic nanoparticles, and liposomes — and their ability to modulate microglial activation, promote a shift from a pro-inflammatory (M1) to an anti-inflammatory (M2) phenotype, and enhance antidepressant efficacy. Preclinical studies have demonstrated that nanoparticle-based systems not only improve drug bioavailability and brain targeting but also potentiate neuroprotective effects by reducing oxidative stress, promoting neurogenesis, and restoring synaptic plasticity. These findings highlight the potential of nanotechnology as a novel approach to precision neuropsychopharmacology. This review aims to provide an integrative perspective on how nanocarrier-based strategies targeting microglia could redefine future therapeutic paradigms for MDD.