Potential neuroprotective activity of Mentha longifolia L. in aluminum chloride-induced rat model of Alzheimer's disease

Kaixinsan regulates neuronal mitochondrial homeostasis to improve the cognitive function of Alzheimer's disease by activating CaMKKβ-AMPK-PGC-1α signaling axis

BACKGROUND

Alzheimer's disease (AD) is a neurodegenerative disease primarily characterized by cognitive impairments. With the intensification of population aging, AD has become a major health concern affecting the elderly. Kaixinsan, a classical traditional Chinese formula, consists of Ginseng Panax et Rhizoma, Polygalae Radix, Poria and Acori Tatarinowii Rhizoma, and is commonly used in clinical for treating memory decline. However, its mechanism remains unclear, which hinders its popularization and application.

METHOD

Morris water maze (MWM) was performed to evaluate the effect of Kaixinsan on improving learning and memory ability in SAMP8 (senescence-accelerated mouse prone 8, an AD model mice) mice. Nissl staining, TdT-mediated dUTP Nick End Labeling (TUNEL) and western blotting (Bax and Bcl-2) were used to confirm the effect of Kaixinsan on the neuronal structure and apoptosis of SAMP8 mice. Ultra performance liquid chromatography coupled with quadrupole time of flight mass spectrometry (UPLC-Q-TOF/MS) was performed to identify the distribution components in brain tissue after administration of Kaixinsan extraction. Based on the identified brain distribution components, the mechanism of Kaixinsan improving the cognitive function was predicted by network pharmacology. Then, using HSP60 as a mitochondrial marker and RBFOX3 as a neuronal marker, immunofluorescence co-localization was used to confirm the effect of Kaixinsan on neuronal mitochondria quantity in SAMP8 mice. Western blotting was employed to access the expression of predicted proteins (AMPK, CaMKKβ, PGC-1α and HSP90) implicated in mitochondrial homeostasis. To further confirm the mechanism of Kaixinsan, SH-SY5Y cell injury model induced by amyloid β - protein fragment 25-35 (Aβ25-35) was replicated and the effect of Kaixinsan - containing serum on apoptosis in injured SH-SY5Y cells was investigated by flow cytometer. The expression level of apoptosis-associated proteins (Bax and Bcl-2) and mitochondrial homeostasis related proteins (AMPK, CaMKKβ, PGC-1α and HSP90) in the presence or absence of CaMKKβ inhibitor (STO-609) were compared.

RESULTS

The results indicate that Kaixinsan can improve the cognitive function of SAMP8 mice, alleviate the hippocampal tissue lesions and inhibit neuron apoptosis. Seventeen brain distribution components of Kaixinsan were identified. Based on the brain distribution components of Kaixinsan, the results of network pharmacology suggest that Kaixinsan may regulate mitochondrial homeostasis through the CaMKKβ-AMPK-PGC-1α signaling axis. In vivo experiments indicated that Kaixinsan could reverse neuronal mitochondrial loss in SAMP8 mice by upregulating CaMKKβ, AMPK, HSP90 and PGC-1α to promote mitochondrial biogenesis and increase the number of neuronal mitochondria. Additionally, the in vitro experiments demonstrated that Kaixinsan can inhibit apoptosis of Aβ25-35 injured SH-SY5Y cells and upregulate mitochondrial homeostasis-related proteins CaMKKβ, AMPK and PGC-1α. However, in addition to CaMKKβ inhibitors, the neuroprotective effect disappeared.

CONCLUSION

The results indicate that Kaixinsan can improve the cognitive function of SAMP8 mice by regulating CaMKKβ-AMPK-PGC-1α signaling axis to maintain mitochondrial homeostasis and inhibit neuronal apoptosis.

Investigating the Anti-inflammatory Effect of Quinoline Derivative: N1-(5-methyl-5H-indolo[2,3-b]quinolin-11-yl)benzene-1,4-diamine Hydrochloride Loaded Soluble Starch Nanoparticles Against Methotrexate-induced Inflammation in Experimental Model

BACKGROUND

It is necessary to develop advanced therapies utilizing natural ingredients with anti-inflammatory qualities in order to lessen the negative effects of chemotherapeutics.

RESULTS

The bioactive N1-(5-methyl-5H-indolo[2,3-b]quinolin-11-yl)benzene-1,4-diamine hydrochloride (NIQBD) was synthesized. After that, soluble starch nanoparticles (StNPs) was used as a carrier for the synthesized NIQBD with different concentrations (50 mg, 100 mg, and 200 mg). The obtained StNPs loaded with different concentrations of NIQBD were coded as StNPs-1, StNPs-2, and StNPs-3. It was observed that, StNPs-1, StNPs-2, and StNPs-3 exhibited an average size of 246, 300, and 328 nm, respectively. Additionally, they also formed with homogeneity particles as depicted from polydispersity index values (PDI). The PDI values of StNPs-1, StNPs-2, and StNPs-3 are 0.298, 0.177, and 0.262, respectively. In vivo investigation of the potential properties of the different concentrations of StNPs loaded with NIQBD against MTX-induced inflammation in the lung and liver showed a statistically substantial increase in levels of reduced glutathione (GSH) accompanied by a significant decrease in levels of oxidants such as malondialdehyde (MDA), nitric oxide (NO), advanced oxidation protein product (AOPP), matrix metalloproteinase 9/Gelatinase B (MMP-9), and levels of inflammatory mediators including interleukin 1-beta (IL-1β), nuclear factor kappa-B (NF-κB) in both lung and liver tissues, and a significant decrease in levels of plasma homocysteine (Hcy) compared to the MTX-induced inflammation group. The highly significant results were obtained by treatment with a concentration of 200 mg/mL. Histopathological examination supported these results, where treatment showed minimal inflammatory infiltration and congestion in lung tissue, a mildly congested central vein, and mild activation of Kupffer cells in liver tissues.

CONCLUSION

Combining the treatment of MTX with natural antioxidant supplements may help reducing the associated oxidation and inflammation.

Biochemical characterization of chamomile essential oil: Antioxidant, antibacterial, anticancer and neuroprotective activity and potential treatment for Alzheimer's disease

Alzheimer's disease (AD) causes dementia among older adults, increasing the global burden of dementia. Therefore, this study investigates the potential neuroprotective, antioxidant, and anticancer effects of chamomile essential oil (CCO) in Alzheimer's disease. CCO's main volatile compounds (VOCs) were α-bisabolol, camazulene, and bisabolol oxide A, representing 81 % of all VOCs. CCO scavenged 93 % of DPPH free radicals and inhibited the pathogenic bacteria, i.e., Staphylococcus aureus and Salmonella typhi, besides reducing 89 % of brain cancer cell lines (U87). Eighty albino rats were randomized into four groups: standard control, Alzheimer's disease group caused by AlCl3, and treated groups. The results indicated that the mean value of tumor necrosis factor α (TNF-α), amyloid precursor protein (APP), amyloid beta (Aβ), caspase-3, & B-cell lymphoma 2 (Bcl-2) was significantly elevated due to the harmful effect of AlCl3; however, CCO downregulated these values, and this effect was attributed to the considerable volatile compounds and phenolic compounds content. Additionally, CCO rats showed a significant increment in noradrenergic (NE), dopaminergic (DO), and serotoninergic systems with relative increases of 50, 50, and 14 % compared to diseased rats. The brain histology of CCO-treated rats showed a significant reduction in neuronal degeneration and improved brain changes, and its histology was close to that of the control brain. The results indicated that CCO offers a new strategy that could be used as an antioxidant and neuroprotective agent for AD due to its considerable contents of antioxidants and anti-inflammatory compounds.

ZBP1 mediates the progression of Alzheimer's disease via pyroptosis by regulating IRF3

Alzheimer's disease (AD) is one of the leading causes of death throughout the world. Z-DNA binding protein 1 (ZBP1), a DNA-related gene, is associated with inflammation, and its expression is altered in AD brain. We aimed to elucidate the exact role of ZBP1 in AD development and its potential regulatory mechanism. First, we constructed both in vivo and in vitro models of AD and investigated the ZBP1 expression profile. A loss-of-function assay was performed by transfecting lentivirus carrying ZBP1 short hairpin RNA (shRNA). By evaluating cell death, oxidative stress, inflammation response and pyroptosis, the function of ZBP1 was validated. Finally, the correlation between ZBP1 and interferon regulatory factor 3 (IRF3) was verified. We also performed rescue experiments to validate the crucial role of IRF3 in ZBP1-mediated AD progression. According to our results, ZBP1 was upregulated in AD rat tissue and AD neurons. Silencing ZBP1 dramatically decreased cell injury, oxidative stress and inflammation in AD neurons and improved the cognitive function of AD rats. Additionally, IRF3 expression and phosphorylation were significantly elevated during AD development and positively correlated with ZBP1. Taken together, silencing ZBP1 suppressed cell injury and pyroptosis of AD neurons and improved cognitive function of AD rats via inhibiting IRF3. These findings might provide a novel insight for AD target diagnosis and therapy.

Bombax ceiba Linn. leaf extract rich in phenolic compounds to mitigate non-alcoholic fatty liver-related complications in experimental model

OBJECTIVES

Obesity, diabetes mellitus, insulin resistance (IR), and hypertriglyceridemia are common features observed in non-alcoholic fatty liver diseases (NAFLD). There is a critical medical necessity to find novel therapeutics that can halt the development of NAFLD.

METHODS

Bombax ceiba Linn. leaf extract was prepared and its phytochemical profile was determined. Standard and high carbohydrate high-fat diets (HCHF) were prepared. Rats were fed HCHF for 18 weeks to induce a non-alcoholic fatty liver (NAFL) model. Forty male rats were divided into control, B. ceiba Linn. leaf extract, NAFL, prophylactic, and treated groups. Serum fasting blood sugar (FBS), insulin, insulin resistance (HOMA-IR), cholesterol, high-density lipoprotein (HDL), triglycerides (TG), low density lipoprotein (LDL), alanine aminotransferase (ALT), aspartate aminotransferase (AST), intelectin-1 (ITLN1), p38 MAP kinase (MAPK), peroxisome proliferator-activated receptor alpha (PPAR-α), and interleukin-6 (IL-6) were evaluated.

RESULTS

Data obtained showed that HCHF-induced NAFL resulting in a significant increase in FBS, serum insulin, HOMA-IR, cholesterol, LDL, TG, ALT, AST, and IL-6 and a significant decrease in serum levels of HDL, ITLN1, p38 MAP kinase, and PPAR-α compared to the control group. The analysis of B. ceiba Linn. leaf extract showed high content of phenol compounds which may cause a significant decrease in the levels of FBS, insulin, HOMA-IR values, lipid profile, and levels of IL-6 while a significant increase in serum levels of LDL, ITLN1, p38 MAP kinase, and PPAR-α compared to the NAFL group.

CONCLUSIONS

B. ceiba Linn. Leaf extract is a highly protective and promising therapeutic agent against inflammation and oxidative stress in the NAFLD model induced by HCHF.

Origanum majorana L. protects against neuroinflammation-mediated cognitive impairment: a phyto-pharmacological study

BACKGROUND

Neuroinflammation and oxidative stress are critical players in the pathogenesis of numerous neurodegenerative diseases, such as Alzheimer's disease (AD) which is responsible for most cases of dementia in the elderly. With the lack of curative treatments, natural phenolics are potential candidates to delay the onset and progression of such age-related disorders due to their potent antioxidant and anti-inflammatory effects. This study aims at assessing the phytochemical characteristics of Origanum majorana L. (OM) hydroalcohol extract and its neuroprotective activities in a murine neuroinflammatory model.

METHODS

OM phytochemical analysis was done by HPLC/PDA/ESI-MSⁿ. Oxidative stress was induced in vitro by hydrogen peroxide and cell viability was measured using WST-1 assay. Swiss albino mice were injected intraperitoneally with OM extract at a dose of 100 mg/kg for 12 days and with 250 μg/kg LPS daily starting from day 6 to induce neuroinflammation. Cognitive functions were assessed by novel object recognition and Y-maze behavioral tests. Hematoxylin and eosin staining was used to assess the degree of neurodegeneration in the brain. Reactive astrogliosis and inflammation were assessed by immunohistochemistry using GFAP and COX-2 antibodies, respectively.

RESULTS

OM is rich in phenolics, with rosmarinic acid and its derivatives being major constituents. OM extract and rosmarinic acid significantly protected microglial cells against oxidative stress-induced cell death (p < 0.001). OM protected against the LPS-induced alteration of recognition and spatial memory in mice (p < 0.001) and (p < 0.05), respectively. Mice that received OM extract prior to the induction of neuroinflammation showed comparable histology to control brains, with no overt neurodegeneration. Furthermore, OM pre-treatment decreased the immunohistochemistry profiler score of GFAP from positive to low positive and COX-2 from low positive to negative in the brain tissue, compared to the LPS group.

CONCLUSION

These findings highlight the potential preventive effects of OM phenolics against neuroinflammation and pave the way toward drug discovery and development for neurodegenerative disorders.

Effects of simultaneous versus post exposure epigallocatechin-3-gallate treatment on aluminum induced neurotoxicity in rat hippocampus: A multi-approach study

Chronic aluminium(Al) exposure can affect the antioxidant and glutaminergic systems through N-methyl-D-aspartate receptors (NMDAR). This study was aimed to investigate the neurotoxic effect of Al through different mechanisms in rat hippocampus and to evaluate the protective role of epigallocatechin gallate (EGCG), a well-known antioxidant, with simultaneous administration of Al,as well as post-treatment after Al exposure.For this purpose, aluminum chloride(AlCl₃) was administered simultaneously with two different EGCG doses for 8 weeks as the first part of the study.In the second part of the study, after 4 weeks of AlCl₃ pre-administration, two different EGCG doses were also administered during four additional weeks as post-treatment.Al administration led to oxidative stress and increased acetylcholinesterase levels.NMDAR subunit mRNA expressions were down-regulated by Al, which was apparent in NMDAR1/2B subunits.Simultaneous EGCG treatment has shown a better neuroprotective effect in terms of these mechanisms and represents novel approach for the prevention of neurodegenerative diseases likely to be induced by Al.

Effects of baicalein with memantine on aluminium chloride-induced neurotoxicity in Wistar rats

Alzheimer's disease is a progressive neurodegenerative condition. It is one of the most common 28 forms of dementia accounting for 60-80% of people suffering from dementia. There are very few medications that are approved for the treatment of Alzheimer's disease. Baicalein, belonging to the flavone subclass of flavonoids, has been reported to have a neuroprotective effect by reducing oxidative stress and neuroinflammation, inhibiting the AChE enzyme, and reducing amyloid protein aggregation and toxicity. Memantine is one of the most important drugs used for treating Alzheimer's disease. The purpose of this work was to study the effect of baicalein with memantine on aluminum chloride-induced neurotoxicity in Wistar rats. Aluminum chloride (100 mg/kg p.o.) was administered for 42 days in male Wistar rats to induce neurotoxicity. Baicalein alone (10 mg/kg) and a combination of baicalein (5 mg/kg and 10 mg/kg) with memantine (20 mg/kg) were administered for 42 days. Treatment of baicalein with memantine showed significant improvement in behavioral parameters. The combination reduced oxidative stress and the formation of β-Amyloid plaques and increased brain-derived neurotrophic factor (BDNF) expression. Based on findings, it can be concluded that treatment with baicalein and memantine may slow the progression of neurodegeneration in rats.

Eicosapentaenoic acid loaded silica nanoemulsion attenuates hepatic inflammation through the enhancement of cell membrane components

Background

Liver inflammation is a multistep process that is linked with cell membrane fatty acids composition. The effectiveness of eicosapentaenoic acid (EPA) undergoes an irreversible change during processing due to their unsaturated nature; so the formation of nanocarrier for EPA is crucial for improving EPA’s bioavailability and pharmacological properties.

Objective

In this study we aimed to evaluate the efficiency of EPA alone or loaded silica nanoemulsion on the management of hepatic inflammation induced by diethyl nitrosamine (DEN) through the enhancement of the cell membrane structure and functions.

Methods

The new formula of EPA was prepared to modify the properties of EPA. Forty-eight male Wistar albino rats were classified into: control, EPA, EPA loaded silica nanoemulsion (EPA–NE), DEN induced hepatic inflammation; DEN induced hepatic inflammation treated with EPA or EPA –NE groups. Plasma tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), liver hydroxyproline (Hyp) content, and liver oxidant and anti-oxidants were estimated. Urinary 8- hydroxyguanozine (8- OHdG) and erythrocyte membrane fatty acids fractions were estimated by High-performance liquid chromatography (HPLC). Also, histopathology studies were done to verify our hypothesis.

Results

It was appeared that administration of EPA, in particular EPA loaded silica nanoemulsion, ameliorated the inflammatory response, increased the activity of the anti-oxidants, reduced levels of oxidants, and improved cell membrane structure compared to hepatic inflammation induced by DEN group. Histopathological examination confirmed these results.

Conclusion

EPA and notably EPA loaded silica nanoemulsion strongly recommended as a promising supplement in the management of hepatic inflammation.