Cognition enhancing effects of Clausena lansium (Lour.) peel extract attenuate chronic restraint stress-induced memory deficit in rats

Phenolic profiles in the peels of three wampee (Clausena lansium (Lour.) Skeels) fruit cultivars and immune-modulatory activity through the cluster of differentiation 14-mitogen activated protein kinase/nuclear factor kappa B pathways

ETHNOPHARMACOLOGICAL RELEVANCE

The peels of wampee (Clausena lansium (Lour.) Skeels) fruits have been ethnomedicinally used to cure malarial fever, coughs, bronchitis, viral hepatitis, and gastrointestinal disorders, suggesting potential immunoprotective and anti-inflammatory properties.

AIM OF THE STUDY

This study aimed to compare the phenolic profiles in the peels of three wampee fruit cultivars and initially reveal the comprehensive immune-modulatory mechanisms of the phenolic fraction.

MATERIALS AND METHODS

The fruits of Golden wampee (GLW), Jixin wampee (JXW) and Guifei wampee (GFW) were collected. Their peels (GLP, JXP, GFP) were used to extract crude phenols (GLPE, JXPE, GFPE). JXPF was a phenolic fraction purified from JXPE using preparative high-performance liquid chromatography, which contained the mixture of various phenolic compounds in JXP. Phenolic contents were quantified using HPLC. The binding receptors and immune-modulatory pathways were investigated in LPS-induced RAW 264.7 cells.

RESULTS

JXP exhibited higher proportions of phenolic compounds, including myricetin-3-O-galactoside, nicotiflorin, rutin, isorhamnetin-3-O-neohesperidoside, isoquercitrin, quercitrin, and 8-hydroxypsoralen. GLPE, JXPE and GFPE reduced LPS-induced overexpression of NO, IL-6 and TNF-α, maintaining these mediators at moderate levels, which indicated immune-modulatory activity. The phenolic compounds in JXPF could occupy the CD14 receptor on macrophage surfaces and finally suppress the phosphorylation of ERK 1/2, p38, JNK, IκBα, and p65 in the MAPK and NF-κB signaling pathways.

CONCLUSIONS

JXW was identified as a superior cultivar with a higher abundance of phenolic compounds in its peels. The phenols derived from wampee peels demonstrated potential as immune-modulatory agents.

Mechanistic insight into neuroprotective effect of standardized ginger chemo varieties from Manipur, India in scopolamine induced learning and memory impaired mice

Alzheimer's disease is a complex neurodegenerative disease characterized by progressive decline in cognitive function and behaviour. Ginger is the rhizome of the plant Zingiber officinale Roscoe, has been an important ingredient of many Ayurveda formulations to treat neurological disorders. The present study aims to estimate the variation of 6-gingerol content in nine different ginger samples collected from Manipur, India, investigate the neuroprotective potential of the most potent ginger sample against scopolamine-induced cognitively impaired mice, and validate the therapeutic claim by molecular docking analysis. High Performance Thin Layer Chromatography (HPTLC) analysis suggested that the sample GV6 had the highest 6-gingerol content with potent in vitro acetylcholnesterase (AChE) (IC50 = 336.10 µg/mL) and butyrylcholinesterase (BChE) (IC50 = 411.73 µg/mL) enzyme inhibitory activity. The neuroprotective potential of GV6 was tested in scopolamine-induced cognitively impaired mice (200 and 400 mg/kg). The behavioral analysis showed that GV6 alleviated the spatial recognition, and short-term and long-term memory in the experimental mice model. GV6 significantly improved brain AChE and BChE activity, acetylcholine (ACh) level, markedly alleviated the antioxidant parameters, and reversed the neuroinflammation. Brain histopathological observations confirmed the presence of organized nerve fibers, improvement of neuronal cell density, and reverse the nucleus shrinkage. Further molecular docking analysis showed that 6-gingerol and galantamine exhibited stable interaction with AChE (-7.5 and - 7.3 kcaL/moL) and BChE (-7.3 and - 8.5 kcaL/moL). The present study emphasizes the quality-related therapeutic importance of ginger samples from Northeast India and demonstrates that administration of GV6 may improve brain cognitive functions by restoring neurotransmitter levels and inflammatory and antioxidant parameters in scopolamine-induced cognitively impaired mice.

The Efficiency of Chitosan Against Tert Butylhydroquinone (TBHQ)-Induced Neurobehavioral Changes and Toxicity Effects in Male Rats

BACKGROUND

We investigated chitosan's protective effects against tertiary butylhydroquinone (TBHQ)-induced toxicity in adult male rats, focusing on cognitive functions and oxidative stress in the brain, liver, and kidneys.

METHODS

Rats were divided into four groups (n = 8/group): (1) Control, (2) Chitosan only, (3) TBHQ only, and (4) Chitosan + TBHQ.

RESULTS

TBHQ exposure led to significant cognitive impairments and increased oxidative stress, marked by elevated malondialdehyde (MDA) and decreased superoxide dismutase (SOD) and glutathione (GSH) levels. Behavioral tests, including the Morris Water Maze (MWM) as well as Passive Avoidance Learning (PAL) tasks, confirmed memory and learning deficits in the TBHQ group. Histopathological analysis showed damage in the brain, liver, and kidney tissues of TBHQ-exposed rats. Chitosan treatment significantly mitigated these effects, reducing oxidative stress markers and preserving tissue integrity. These findings suggest that chitosan's antioxidant properties may provide a therapeutic benefit against TBHQ-induced neurotoxicity and organ damage.

CONCLUSIONS

These findings suggest that chitosan exerts potent neuroprotective effects, potentially through its antioxidant and anti-inflammatory properties, and could serve as a therapeutic agent against TBHQ-induced toxicity.

Insights into Tissue-Specific Specialized Metabolism in Wampee (Clausena lansium (Lour.) Skeels) Varieties

Wampee (Clausena lansium (Lour.) Skeels) has natural bioactive components with diverse health benefits, but its detailed metabolism and tissue distribution are not fully understood. Here, widely targeted metabolomics analysis methods were employed to analyze the wampee fruit (peel, pulp, and seed) of 17 different varieties. A total of 1286 metabolites were annotated, including lipids, flavonoids, polyphenols, carbazole alkaloids, coumarins, and organic acids, among others. The quantitative analysis and matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) analysis indicated remarkable variations in metabolite categories and content in the peel, pulp, and seed of wampee fruit. Additionally, the difference analysis found that the metabolic components of peel contributed dominantly to the differences among varieties, and 7 potential biomarkers were identified. In this study, a comprehensive metabolome landscape of wampee fruit was established, which provided important information for the isolation and identification of functional components, food industry application, and nutritional improvement breeding.

RNA-Seq-Based Transcriptomics and GC-MS Quantitative Analysis Reveal Antifungal Mechanisms of Essential Oil of Clausena lansium (Lour.) Skeels Seeds against Candida albicans

Infections caused by Candida albicans (C. albicans) and increasing resistance to commonly used drugs lead to a variety of mucosal diseases and systemic infectious diseases. We previously confirmed that the essential oil of Clausena lansium (Lour.) Skeels seeds (CSEO) had antifungal activity against C. albicans, but the detailed mechanism between the chemical components and antifungal activity is unclear. In this study, a quantitative analysis of five volatile components of CSEO, including sabinene, α-phellandrene, β-phellandrene, 4-terpineol, and β-caryophyllene, was carried out using the gas chromatography-mass spectrometry (GC-MS) method. Both the broth dilution and kinetic growth methods proved that the antifungal activity of CSEO against fluconazole-resistant C. albicans was better than that of its main components (sabinene and 4-terpineol). To further investigate the inhibitory mechanism, the transcriptional responses of C. albicans to CSEO, sabinene, and 4-terpineol treatment were determined based on RNA-seq. The Venn diagram and clustering analysis pattern of differential expression genes showed the mechanism of CSEO and 4-terpineol's anti-C. albicans activity might be similar from the perspective of the genes. Functional enrichment analysis suggested that CSEO regulated adherence-, hyphae-, and biofilm-formation-related genes, which may be CSEO's active mechanism of inhibiting the growth of fluconazole-resistant C. albicans. Overall, we preliminarily revealed the molecular mechanism between the chemical components and the antifungal activity of CSEO against C. albicans. This study provides new insights to overcome the azole resistance of C. albicans and promote the development and application of C. lansium (Lour.) Skeels seeds.

Gallic acid ameliorates behavioral dysfunction, oxidative damage, and neuronal loss in the prefrontal cortex and hippocampus in stressed rats

Gallic acid (GA) is known to be a natural phenolic compound with antioxidant and neuroprotective effects. This study aims to investigate the impact of GA against restraint stress-induced oxidative damage, anxiety-like behavior, neuronal loss, and spatial learning and memory impairment in male Wistar rats. The animals were divided into four groups (n = 8) and subjected to restraint stress for 4 h per day for 14 consecutive days or left undisturbed (control without inducing stress). In the treatment group, the animals were treated with 2 mL normal saline plus 100 mg/kg GA per day for 14 consecutive days (STR + GA group). The animals received the drug or normal saline by gavage 2 h before inducing restraint stress. ELISA assay measured oxidative stress factors. Elevated-plus maze and Morris water maze tests assessed anxiety-like behavior and spatial learning and memory, respectively. Also, neuronal density was determined using Nissl staining. Restraint stress significantly increased MDA and reduced the activities of GPX and SOD in the stressed rats, which were reserved by treatment with 100 mg/kg GA. Restraint stress markedly enhanced the anxiety-like behavior and spatial learning and memory impairment that were reserved by GA. In addition, treatment with GA reduced the neuronal loss in the stressed rats in the hippocampus and prefrontal cortex (PFC) regions. Taken together, our findings suggest that GA has the potential to be used as a good candidate to attenuate neurobehavioral disorders as well as neuronal loss in the hippocampus and PFC induced by restraint stress via reducing oxidative damage.

Comprehensive Review of Phytochemical Profiles and Health-Promoting Effects of Different Portions of Wampee (Clausena lansium)

Clausena lansium, commonly known as wampee, is a subtropical fruit from the Rutaceae family characterized by its high nutrient content and numerous bioactive substances. This low-fat fruit is abundant in fiber, vitamins, minerals, and essential amino acids. Wampee has been found to contain several bioactive compounds, including essential oils, phenolic compounds, and alkaloids. These bioactive constituents provide numerous health-enhancing properties, such as antioxidant, neuroprotective, anticarcinogenic, anti-inflammatory, hepatoprotective, antidiabetic, and antimicrobial effects. The relationship between these compounds and their impacts on health has been explored in various studies. While the disease-prevention efficacy of C. lansium has been established, additional research is necessary to elucidate the precise mechanisms and metabolic pathways involved. This paper presents a comprehensive review of wampee, focusing on its bioactive compounds, the beneficial effects derived from its consumption, and the evidence supporting the development of wampee-based functional foods in future studies.

Pinostrobin alleviates chronic restraint stress‑induced cognitive impairment by modulating oxidative stress and the function of astrocytes in the hippocampus of rats

Chronic stress has been recognized to induce the alterations of neuronal and glial cells in the hippocampus, and is thus implicated in cognitive dysfunction. There is increasing evidence to indicate that natural compounds capable of exerting neuroprotective and antioxidant activities, may function as potential therapeutic agents for cognitive impairment. The present study examined the neuroprotective effects of pinostrobin from Boesenbergia rotunda (L.) against chronic restraint stress (CRS)-induced cognitive impairment associated with the alterations of oxidative stress, neuronal density and glial fibrillary acidic protein (GFAP) of astrocytes in the hippocampus. For this purpose, male Wistar rats were administered once daily with pinostrobin (20 and 40 mg/kg, per os) prior to exposure to CRS (6 h/day) for 21 days. The cognitive behaviors, the concentration of malondialdehyde, and the activities of superoxide dismutase and catalase were determined. Histologically, the alterations in astrocytic GFAP and excitatory amino acid transporter 2 (EAAT2) in the hippocampus were examined. The results revealed that pinostrobin potentially attenuated cognitive impairment in the Y-maze and in novel object recognition tests, with a reduction in oxidative stress. Furthermore, pinostrobin effectively increased neuronal density, as well as the immunoreactivities of GFAP and EAAT2 in the hippocampus. Taken together, these findings indicate that treatment with pinostrobin alleviates chronic stress-induced cognitive impairment by exerting antioxidant effects, reducing neuronal cell damage, and improving the function of astrocytic GFAP and EAAT2. Thus, pinostrobin may have potential for use as a neuroprotective agent to protect against chronic stress-induced brain dysfunction and cognitive deficits.

Neuroprotective Effects of Agri-Food By-Products Rich in Phenolic Compounds

Neurodegenerative diseases are known for their wide range of harmful conditions related to progressive cell damage, nervous system connections and neuronal death. These pathologies promote the loss of essential motor and cognitive functions, such as mobility, learning and sensation. Neurodegeneration affects millions of people worldwide, and no integral cure has been created yet. Here, bioactive compounds have been proven to exert numerous beneficial effects due to their remarkable bioactivity, so they could be considered as great options for the development of new neuroprotective strategies. Phenolic bioactives have been reported to be found in edible part of plants; however, over the last years, a large amount of research has focused on the phenolic richness that plant by-products possess, which sometimes even exceeds the content in the pulp. Thus, their possible application as an emergent neuroprotective technique could also be considered as an optimal strategy to revalorize these agricultural residues (those originated from plant processing). This review aims to summarize main triggers of neurodegeneration, revise the state of the art in plant extracts and their role in avoiding neurodegeneration and discuss how their main phenolic compounds could exert their neuroprotective effects. For this purpose, a diverse search of studies has been conducted, gathering a large number of papers where by-products were used as strong sources of phenolic compounds for their neuroprotective properties. Finally, although a lack of investigation is quite remarkable and greatly limits the use of these compounds, phenolics remain attractive for research into new multifactorial anti-neurodegenerative nutraceuticals.