Astrocytes are the major glial cells in the human brain and provide crucial metabolic and trophic support to neurons. The amyloid-β peptide (Aβ) alter the morphological and functional properties of astrocytes and induce inflammation and calcium dysregulation, contributing to Alzheimer's disease (AD) pathology. Recent studies highlight the role of Toll-like receptor (TLR) 4/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling in inflammation. Reactive oxygen species (ROS) generated due to Aβ, induce apoptosis in the brain cells worsening AD progression. Astrocytic cell surface receptors, such as purinergic receptors (P2Y1 and P2Y2), metabotropic glutamate receptor (mGLUR)5, α7 nicotinic acetylcholine receptor (α7nAChR), and N-methyl-d-aspartate receptors (NMDARs), have been suggested to interact with inositol trisphosphate receptor (IP₃R) on the endoplasmic reticulum (ER) to induce Ca²⁺ movement from ER to cytoplasm, causing Ca²⁺ dysregulation. We found that the citrus flavonoid nobiletin (NOB) protected primary astrocytes from Aβ42-induced cytotoxicity and inhibited TLR4/NF-κB signaling in Aβ42-induced primary rat astrocytes. NOB was found to regulate Aβ42-induced ROS levels through Keap1-Nrf2 pathway. The receptors P2Y1, P2Y2, mGLUR5, α7nAChR, and NMDARs induced intracellular Ca²⁺ levels by activating IP₃R and NOB regulated them, thereby regulating intracellular Ca²⁺ levels. Molecular docking analysis revealed a possible interaction between NOB and IP₃R in IP₃R regulation. Furthermore, RNA sequencing revealed various NOB-mediated biological signaling pathways, such as the AD-presenilin, AD-amyloid secretase, and Wnt signaling pathway, suggesting possible neuroprotective roles of NOB. To conclude, NOB is a promising therapeutic agent for AD and works by modulating AD pathology at various levels in Aβ42-induced primary rat astrocytes.

Parkinson’s disease (PD) is a widespread age-related neurodegenerative disorder characterized by the presence of an aggregated protein, α-synuclein (α-syn), which is encoded by the SNCA gene and localized to presynaptic terminals in a normal human brain. The α-syn aggregation is induced by the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mitochondrial neurotoxin and is therefore used to mimic PD-like pathology in various in vitro and in vivo models. However, in vitro PD-like pathology using α-syn and MPTP in human microglial cells has not yet been reported. Malvidin-3-O-glucoside (M3G) is a major anthocyanin primarily responsible for pigmentation in various fruits and beverages and has been reported to possess various bioactivities. However, the neuroprotective effects of M3G in humanized in vitro PD-like pathologies have not been reported. Therefore, individual and co-treatments of α-syn and MPTP in a human microglial (HMC3) cell line were used to establish a humanized PD-like pathology model in vitro. The individual treatments were significantly less cytotoxic when compared to the α-syn and MPTP co-treatment. This study examined the neuroprotective effects of M3G by treating HMC3 cells with α-syn (8 μg/mL) and MPTP (2 mM) individually or in a co-treatment in the presence or absence of M3G (50 μM). M3G demonstrated anti-apoptotic, anti-inflammatory, and antioxidative properties against the α-syn- and MPTP-generated humanized in vitro PD-like pathology. This study determined that the cytoprotective effects of M3G are mediated by nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase (HO)-1 signaling.

Codonopsis lanceolata has long been used in traditional medicine across East Asia; however, recent scientific investigations have increasingly highlighted its broad therapeutic potential. This review provides an updated and comprehensive overview of the pharmacological properties of C. lanceolata and its bioactive constituents, focusing on their roles in disease prevention and therapy. Evidence from in vitro, in vivo, and limited clinical studies suggests that C. lanceolata possesses antidiabetic, anti-obesity, and anti-cancer properties while showing protective effects in experimental models of cardiovascular dysfunction, liver injury, neurodegenerative disorders, skeletal muscle atrophy, and pulmonary damage. Additionally, its immunomodulatory effects contribute to improved host defense and regulation of inflammatory responses. These diverse actions are mediated by mechanisms involving antioxidant activity, inhibition of inflammatory signaling, regulation of metabolic pathways, modulation of apoptosis, and maintenance of tissue integrity. Despite promising findings, challenges remain regarding extract standardization, identification of key active compounds, and the translation of preclinical results into clinical efficacy. Future research integrating molecular, pharmacokinetic, and clinical approaches is essential to clarify the therapeutic value and establish its potential as a nutraceutical or therapeutic agent. This review highlights the promising pharmacological potential and identifies key directions for future research to support its potential application in modern medicine.

Dry eye disease (DED) is a multifactorial ocular surface disorder characterized by inflammation, oxidative stress, tear film instability, and secretory dysfunction. This study investigated the protective effects of Lute-gen^®, a lutein and zeaxanthin-based formulation, in both in vitro and in vivo DED models. Human corneal epithelial (HCE-T) cells were stimulated with TNF-α, while dry eye was induced in female Sprague–Dawley rats using subcutaneous scopolamine (SCP) administration. In HCE-T cells, Lute-gen^® showed no cytotoxicity, restored cell viability, reduced intracellular ROS, and was associated with increased expression of antioxidant-related markers (Nrf2, HO-1, SOD, CAT, and GPx), reduced expression of inflammatory mediators (TLR4/MyD88/NF-κB/NLRP3), and increased expression of AQP3 and AQP5. In SCP-induced rats, Lute-gen^® significantly improved tear secretion and reduced corneal fluorescein staining. Histopathological analyses revealed restoration of conjunctival goblet cells, mucin staining, corneal epithelial integrity, acinar area and cell density, and lacrimal gland architecture, with reduced inflammatory infiltration. Immunofluorescence further demonstrated reduced TLR4 and MMP9 immunoreactivity and decreased CD68⁺ inflammatory cell infiltration. Molecular analyses showed reduced expression of inflammatory cytokines and NF-κB/MAPK/MMP signaling-related inflammatory mediators, together with restoration of AQP1, AQP3, and AQP5 expression in corneal tissues. Collectively, these findings suggest that Lute-gen^® treatment was associated with improvements in dry eye-related pathological changes, including restoration of antioxidant-related markers, attenuation of inflammatory responses, restoration of aquaporin expression, and preservation of ocular surface and lacrimal gland integrity. These preclinical findings support further mechanistic investigations and the future clinical evaluation of Lute-gen^® as a potential nutritional intervention for dry eye disease.