Potential Anti-Gouty Arthritis of Citronella Essential Oil and Nutmeg Essential Oil through Reducing Oxidative Stress and Inhibiting PI3K/Akt/mTOR Activation-Induced NLRP3 Activity.

Citronella and Nutmeg are two common spices used for seasoning and medicinal purposes, both of which have significant economic value. This study aimed to investigate whether Citronella essential oil and Nutmeg essential oil (NEO) can ameliorate monosodium urate (MSU)-induced gouty arthritis in rats and the potential mechanisms. The results showed that CEO and NEO reduced swelling and redness at joint sites, inhibited neutrophil infiltration, and limited proinflammatory mediator secretion in mice with MSU-induced gouty arthritis. Based on the results of network pharmacology, molecular docking, and western blotting, CEO and NEO may exert anti-gouty arthritis effects by reducing the expression of reactive oxygen species and oxidative stress and downregulating the phosphorylation of the PI3K/AKT/mTOR signaling pathway, thereby inhibiting the production of the NLRP3 inflammasome and inhibiting the production of inflammatory cytokines. Therefore, these two essential oils show potential for use as adjuvant treatments for gouty arthritis in specific aromatherapy products or food seasonings.

Antioxidative properties of fish roe peptides combined with polyphenol on the fish oil oleogel.

BACKGROUND: This study aimed to investigate the effects of large yellow croaker (Larimichthys crocea) roe protein hydrolysate (LYCPH)-polyphenol (catechin (CA), gallic acid (GA), and tannic acid (TA)) conjugates on the oxidative stability of fish oil in an oleogel system. RESULTS: Scanning electron microscopy and Fourier transform infrared spectroscopy suggested that the LYCPH-polyphenol conjugates were nearly spherical and non-covalent and that covalent effects could coexist between LYCPH and polyphenols. LYCPH-TA exhibited the highest ABTS scavenging, reducing capacities, and emulsifying stability. Raman spectra and chemometrics revealed that LYCPH-TA loaded with oleogels had the best oxidative stability. Additionally, 32 volatile compounds were identified in fish oil by headspace gas chromatography-ion mobility spectrometry. CONCLUSION: Overall, this study demonstrated that fish oil oleogels loaded with LYCPH-polyphenol conjugates could inhibit fish oil oxidation. © 2022 Society of Chemical Industry.

Integrated lipidomic and transcriptomic analyses reveal the mechanism of large yellow croaker roe phospholipids on lipid metabolism in normal-diet mice.

Large yellow croaker roe phospholipids (LYCRPLs) could regulate the accumulation of triglycerides and blood lipid levels. However, there exists little research on the mechanism of LYCRPLs on lipid metabolism in normal-diet mice. In this work, the mice on a normal diet were given low-dose, medium-dose, and high-dose LYCRPLs by intragastric administration for 6 weeks. At the same time, the physiological and biochemical indicators of the mice were determined, and the histomorphological observation of the liver and epididymal fat was carried out. In addition, we examined the gene expression and lipid metabolites in the liver of mice using transcriptomic and lipidomic and performed a correlation analysis. The results showed that LYCRPLs regulated the lipid metabolism of normal-diet mice by affecting the expression of the glycerolipid metabolism pathway, insulin resistance pathway, and cholesterol metabolism pathway. This study not only elucidated the main pathway by which LYCRPLs regulate lipid metabolism, but also laid a foundation for exploring LYCRPLs as functional food supplements.

Oxidative stability of marine phospholipids derived from large yellow croaker roe.

Large yellow croaker roe phospholipids (LYCPLs) have various functions and high nutritional value, which are expected to be functional foods ingredients. The aim of this study is to investigate the oxidative stability of LYCPLs at different temperatures (100 °C, 140 °C and 180 °C) in terms of peroxide value (POV), thiobarbituric acid-reactive substances value (TBARS), acid value (AV) and fatty acids compositions of phospholipids. The volatile compounds were also identified and analyzed via headspace solid-phase microextraction-gas chromatography-mass spectroscopy (HS-SPME-GC-MS) and headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS). The results showed that the highest POV was 192.92, 133.70 and 121.25 meq/kg at 100 °C, 140 °C and 180 °C within 10-20 min, respectively, then fell along with the increment of heating time, while the highest TBARS was 6.38, 7.66 and 8.19 mg/kg at 30 min, respectively. The AV was increased, but monounsaturated fatty acid and polyunsaturated fatty acid content were decreased with the increment of temperatures. A total of 94 volatile compounds were identified, and the content of alkanes, aldehydes, and heterocyclic compounds were reasonably increased, while the aromatic compound and amide compound content were decreased when LYCPLs heated at 180 °C. The present research improves the comprehensive understanding of oxidative stability of marine phospholipids.

Rapamycin prevents cerebral stroke by modulating apoptosis and autophagy in penumbra in rats.

Objective: Whether activation or inhibition of the mTOR pathway is beneficial to ischemic injury remains controversial. It may result from the different reaction of ischemic penumbra and core to modulation of mTOR pathway after cerebral ischemia-reperfusion injury in rats. Methods: Longa's middle cerebral artery occlusion (MCAO) method was conducted to induce the focal cerebral ischemia-reperfusion. Western blot analysis was used to examine the protein expression involving mTOR pathway, apoptosis, and autophagy-related proteins. TTC staining and Fluoro-Jade B staining was conducted to detect the infarct volume and cell apoptosis, respectively. Neurological function was measured by modified neurological severity score and left-biased swing. Results: mTOR signaling pathway was activated in ischemic penumbra and decreased in ischemic core after ischemia and ischemia-reperfusion. Ischemia-reperfusion injury induced the increase in cleaved caspase 9 and caspase 3 both in ischemic penumbra and in ischemic core, whereas the expression of phosphorylated ULK1, Beclin 1 and LC3-II was decreased. Rapamycin pre or postadministration inhibited the overactivation of mTOR pathway in ischemic penumbra. Ameliorated neurological function and reduced infarct volume were observed after pre or postrapamycin treatment. Rapamycin markedly decreased the number of FJB-positive cells and the expression of cleaved caspase-3 and cleaved caspase-9 proteins as well as increased the activation of autophagy reflected by ULK1, Beclin-1 and LC3. Interpretation: mTOR signaling pathway was activated in ischemic penumbra after cerebral ischemia-reperfusion injury in rats. mTOR inhibitor rapamycin significantly decreased the mTOR activation and infarct volume and subsequently improved neurological function. These results may relate to inhibition of neuron apoptosis and activation of autophagy.

Effect of Chronic Administration of Low Dose Rapamycin on Development and Immunity in Young Rats.

Mammalian target of rapamycin (mTOR) regulates cell growth, cell differentiation and protein synthesis. Rapamycin, an inhibitor of mTOR, has been widely used as an immunosuppressant and anti-cancer drug. Recently, mTOR inhibitors have also been reported to be a potential anti-epileptic drug, which may be effective when used in young patients with genetic epilepsy. Thus, a suitable dose of rapamycin which can maintain the normal function of mTOR and has fewer side effects ideally should be identified. In the present study, we first detected changes in marker proteins of mTOR signaling pathway during development. Then we determined the dose of rapamycin by treating rats of 2 weeks of age with different doses of rapamycin for 3 days and detected its effect on mTOR pathway. Young rats were then treated with a suitable dose of rapamycin for 4 weeks and the effect of rapamycin on mTOR, development and immunity were investigated. We found that the expression of the marker proteins of mTOR pathway was changed during development in brain hippocampus and neocortex. After 3 days of treanent, 0.03 mg/kg rapamycin had no effect on phospho-S6, whereas 0.1, 0.3, 1.0 and 3.0 mg/kg rapamycin inhibited phospho-S6 in a dose-dependent manner. However, only 1.0 mg/kg and 3.0 mg/kg rapamycin inhibited phospho-S6 after 4 weeks treatment of rapamycin. Parallel to this result, rats treated with 0.1 and 0.3 mg/kg rapamycin had no obvious adverse effects, whereas rats treated with 1.0 and 3.0 mg/kg rapamycin showed significant decreases in body, spleen and thymus weight. Additionally, rats treated with 1.0 and 3.0 mg/kg rapamycin exhibited cognitive impairment and anxiety as evident by maze and open field experiments. Furthermore, the content of IL-1ß, IL-2, IFN-γ, TNF-α in serum and cerebral cortex were significantly decreased in 1.0 and 3.0 mg/kg rapamycin-treated rats. The expression of DCX was also significantly decreased in 1.0 and 3.0 mg/kg rapamycin-treated rats. However, rats treated with 1.0 mg/kg rapamycin exhibited fewer and milder side effects than those treated with 3.0 mg/kg. In summary, all these data suggest that there is not a rapamycin dose that can inhibit mTOR for epilepsy without causing any side effects, but 1 mg/kg may be the optimal dose for young rats for suppressing mTOR with relatively few side effects.

Neuroprotective effects of flavonoids extracted from licorice on kainate-induced seizure in mice through their antioxidant properties.

A relationship between status epilepticus (SE) and oxidative stress has recently begun to be recognized. To explore whether the flavonoids extracted from licorice (LFs) have any protective effect on kainate (KA)-induced seizure in mice, we treated mice with LFs before and after KA injection. In KA-treated mice, we found that superoxide dismutase (SOD) activity decreased immediately after the onset of seizure at 1 h and then increased at 6 h. It returned to baseline 1 d after seizure and then increased again at 3, 7, and 28 d, while malondialdehyde (MDA) content remained at a high level at 1 h, 6 h, 3 d, 7 d, and 28 d, indicating a more oxidized status related to the presence of more reactive oxygen species (ROS). Treatment with LFs before KA injection reversed the seizure-induced change in SOD activity and MDA content at 1 h, 6 h, 3 d, 7 d, and 28 d. Treatment with LFs after seizure decreased KA-induced SOD activity and MDA content at 7 and 28 d. Also, LF pre- and post-KA treatments decreased seizure-induced neuronal cell death. Subsequently, Morris water maze tests revealed that the escape latency was significantly decreased and the number of target quadrant crossings was markedly increased in the LF-treated groups. Thus, our data indicate that LFs have protective effects on seizure-induced neuronal cell death and cognitive impairment through their anti-oxidative effects.

[Rapamycin improves learning and memory ability in ICR mice with pilocarpine-induced temporal lobe epilepsy].

OBJECTIVE: To investigate the effect of rapamycin, an mTOR inhibitor, on learning and memory ability of mice with pilocarpine (PILO)-induced seizure. METHODS: One hundred and sixty male adult ICR mice were randomly grouped as vehicle control (n=20), rapamycin control (n=20), PILO model (n=40), rapamycin pre-treatment (n=40) and rapamycin post-treatment (n=40). PILO model and rapamycin treatment groups were injected with PILO to induce temporal lobe seizure. Rapamycin was administrated for 3 days before or after seizure. Morris water maze, Y maze and open field were used for the assessment of learning and memory, and FJB and Timm staining were conducted to detect the neuronal cell death and mossy fiber sprouting, respectively. RESULTS: No significant cell death was observed in the mice with PILO-induced seizure. The learning and memory were impaired in mice 7 to 10 days after PILO-induced seizure, which was evident by prolongation of avoiding latency (P<0.05), decrease in number of correct reaction (P<0.01) and number of crossing (P<0.05). Treatment with rapamycin both pre-and post- PILO injection reversed seizure-induced cognitive impairment. In addition, rapamycin inhibited the mossy fiber sprouting after seizure (P<0.001). CONCLUSION: Rapamycin improves learning and memory ability in ICR mice after PILO-induced seizure, and its mechanism needs to be further studied.

[Comparison of seizure induced by different drugs in ICR Mice].

OBJECTIVE: To compare seizure induced by different epileptic drugs in ICR mice. METHODS: Male adult ICR mice were injected with pilocarpine (Pilo), kainic acid (KA) and pentylenetetrazole (PTZ) to induce status epilepticus (SE). After 2 h of SE, seizures were terminated by injection of diazepam. Mice were sacrificed and sectioned for assessment of neuronal cell death by Fluro-Jade B staining after 7 d and mossy fiber sprouting by Timm staining after 28 d, respectively. Spontaneous seizures were detected by video for 28 d. RESULTS: Pilo and KA induced typical SE in ICR mice, which was identical to those observed in rats and C57/BL6 mice. Timm staining showed evident mossy fiber sprouting in both Pilo and KA treated mice. The incidences of spontaneous seizure were 57.1% and 35.7% in Pilo and KA treated mice, respectively. Mice treated with PTZ represented kindling model. No mossy fiber sprouting and spontaneous seizures were observed. No cell death was detected in all three groups. CONCLUSION: Similar seizure pattern is observed in ICR mice as in rats and C57/BL6 mice. Both Pilo and KA model are the ideal models for chronic temporal lobe epilepsy. ICR mice can be widely used as a cheaper substitute in epilepsy research.