Morinda officinalis oligosaccharides mitigate depression-like behaviors in hypertension rats by regulating Mfn2-mediated mitophagyLixuan Yang, Yutian Ao, Yannan Li et al.|Journal of Neuroinflammation|2023 OBJECTIVE: Patients with hypertension have a risk of depression. Morinda officinalis oligosaccharides (MOOs) have anti-depressant properties. In this study, we aimed to determine whether MOOs can improve the symptoms of depression in individuals with hypertension. METHODS: Dahl salt-sensitive rats fed with a high-salt diet were stimulated by chronic unpredictable mild stress to mimic hypertension with depression. Primary astrocytes and neurons were isolated from these rats. Astrocytes underwent LPS stimulation to simulate the inflammatory astrocytes during depression. MOOs were administrated at 0.1 mg/g/day in vivo and 1.25, 2.5, and 5 mg/mL in vitro. Mitophagy was inhibited using 5 mM 3-methyladenine (3-MA). Astrocyte-mediated neurotoxicity was detected by co-culturing astrocytes and neurons. RESULTS: MOOs decreased systolic pressure, diastolic pressure, and mean arterial pressure, thereby improving depression-like behavior, including behavioral despair, lack of enthusiasm, and loss of pleasure during hypertension with depression. Furthermore, MOOs inhibited inflammation, astrocytic dysfunction, and mitochondrial damage in the brain. Then, MOOs promoted autophagosome and lysosome enriched in mitochondria in LPS-stimulated astrocytes. MOOs suppressed mitochondrial damage and the release of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-1β in astrocytes undergoing LPS stimulation. Importantly, MOOs rescued the impaired neurons co-cultured with astrocytes. The effects of MOOs on LPS-stimulated astrocytes were reversed by 3-MA. Finally, MOOs upregulated LPS-downregulated Mfn2 expression in astrocytes. Mfn2 inhibition partly reversed the effects of MOOs on hypertension with depression. Intriguingly, Mfn2 suppression activated PI3K/Akt/mTOR pathway during MOOs treatment. CONCLUSIONS: Astrocytes develop neuroinflammation in response to mitochondrial damage during hypertension with depression. MOOs upregulated Mfn2 expression to activate the PI3K/Akt/mTOR pathway-mediated mitophagy, thereby removing impaired mitochondria in astrocytes. HIGHLIGHTS: 1. MOOs have anti-hypertensive and anti-depressive properties. 2. MOOs inhibit inflammation and injury in astrocytes during hypertension with depression. 3. MOOs induce mitophagy activation in inflammatory astrocytes with mitochondrial damage. 4. MOOs upregulate Mfn2 expression in astrocytes. 5. Mfn2 activates mitophagy to resist mitochondrial damage in astrocytes.
Ginsenoside Rg1 Reduced Microglial Activation and Mitochondrial Dysfunction to Alleviate Depression-Like Behaviour Via the GAS5/EZH2/SOCS3/NRF2 AxisJunnan Li, Wei Gao, Zhonghui Zhao et al.|Molecular Neurobiology|2022 Ginsenoside Rg1 is the principal active ingredient in ginseng. The antidepressant effects of Rg1 have been validated; however, the specific underlying mechanism of this effect needs further research. Rats were subjected to the chronic restraint stress (CRS) depression model. Rg1, or a positive control drug, was administered to the rats. Depression-like behaviours were evaluated through behavioural experiments. Cytokine, mRNA, protein, ATP, and mitochondria DNA levels were detected using the indicated methods. Lentivirus-packaged plasmids were injected into the rat brain for GAS5 overexpression or knockdown. In vitro mitochondrial dysfunction was evaluated by detecting mitochondrial reactive oxygen species and mitochondrial membrane potential. Direct interaction between GAS5 and EZH2 was validated by RNA immunoprecipitation and RNA pull-down assay. The enrichment of EZH2 and H3K27me3 was evaluated through chromatin immunoprecipitation quantitative real-time PCR. Rg1 treatment alleviated depression-like behaviours, microglial activation, and mitochondrial dysfunction in CRS rats. Similarly, GAS5 knockdown revealed a similar protective effect of Rg1 treatment. GAS5 overexpression in the rat brain compromised the protective effect of Rg1 treatment. Moreover, Rg1 treatment or GAS5 knockdown attenuated microglial activation and mitochondrial dysfunction in vitro. Mechanically, GAS5 was suppressed SOCS3 and NRF2 expression by facilitating EZH2-mediated transcriptional repression. Rg1 attenuated microglial activation and improved mitochondrial dysfunction in depression by downregulating GAS5 expression. Mechanically, GAS5 might regulate microglial activation and mitochondrial dysfunction via the epigenetic suppression of NRF2 and SOCS3.
Ginsenoside Rb1 protects hippocampal neurons in depressed rats based on mitophagy-regulated astrocytic pyroptosisY.-D. Li, Junnan Li, Lixuan Yang et al.|Phytomedicine|2023 Shugan granule contributes to the improvement of <scp>depression‐like</scp> behaviors in chronic restraint stress‐stimulated rats by altering gut microbiotaJunnan Li, Yannan Li, Wenzhe Duan et al.|CNS Neuroscience & Therapeutics|2022 AIM: The investigation aims to evaluate the potential effect of Shugan Granule (SGKL) on the gut, brain, and behaviors in rats exposed to chronic restraint stress (CRS). METHODS: The fecal microbiota and metabolite changes were studied in rats exposed to CRS and treated with SGKL (0.1 mg/kg/day). Depressive behaviors of these rats were determined through an open-field experiment, forced swimming test, sucrose preference, and weighing. Moreover, LPS-stimulated microglia and CRS-stimulated rats were treated with SGKL to investigate the regulation between SGKL and the PI3K/Akt/pathway, which is inhibited by LY294002, a PI3K inhibitor. RESULTS: (i) SGKL improved the altered behaviors in CRS-stimulated rats; (ii) SGKL ameliorated the CRS-induced neuronal degeneration and tangled nerve fiber and also contributed to the recovery of intestinal barrier injury in these rats; (iii) SGKL inhibited the hippocampus elevations of TNF-α, IL-1β, and IL-6 in response to CRS modeling; (iv) based on the principal coordinates analysis (PCoA), SGKL altered α-diversity indices and shifted β-diversity in CRS-stimulated rats; (v) at the genus level, SGKL decreased the CRS-enhanced abundance of Bacteroides; (vi) Butyricimonas and Candidatus Arthromitus were enriched in SGKL-treated rats; (vii) altered gut microbiota and metabolites were correlated with behaviors, inflammation, and PI3K/Akt/mTOR pathway; (viii) SGKL increased the LPS-decreased phosphorylation of the PI3K/Akt/mTOR pathway in microglia and inhibited the LPS-induced microglial activation; (ix) PI3K/Akt/mTOR pathway inactivation reversed the SGKL effects in CRS rats. CONCLUSION: SGKL targets the PI3K/Akt/mTOR pathway by altering gut microbiota and metabolites, which ameliorates altered behavior and inflammation in the hippocampus.
Mental Health and Related Factors of Adolescent Students During Coronavirus Disease 2019 (COVID-19) PandemicTian’ge Lu, Yao Yu, Zhonghui Zhao et al.|Psychiatry Investigation|2022 OBJECTIVE: Adolescents are at a special stage of physical and mental development, which is a susceptible period for mental disorders. Since the outbreak of coronavirus pneumonia in December 2019, long term stress may have negative effects on the mental health of the adolescents. In the context of the coronavirus disease 2019 (COVID-19), the study was designed to investigate the mental and psychological health of adolescents in China and its possible related factors. METHODS: A cross-sectional study design was adopted using a structured questionnaire which were distributed through the Internet to measure depression, anxiety, life events and stress related factors. Descriptive statistics and multiple regression analyses were conducted to process the data. RESULTS: The final sample comprised 795 adolescents. The total detection rate of depression was 76.48% and the total detection rate of anxiety was 33.08%. ANOVA showed that there were significant differences in depression scores in terms of gender, anxiety scores, history of mental disorders, COVID-19 knowledge reserve, family and social contradictions (p<0.05). And there were significant differences in anxiety scores in terms of gender, depression scores, mental health knowledge reserves, family and social contradictions (p<0.05). Multiple regression analysis showed that anxiety score, health status and COVID-19 knowledge reserve were positively associated with depression score (p<0.01), and history of psychosocial disorders was negatively associated with depression score (p<0.05); depression score, family and social contradictions were significantly positively correlated with anxiety score (p<0.01), and history of mental disorders was significantly negatively correlated with SDS score (p<0.01). CONCLUSION: During the outbreak of COVID-19, adolescent students with better understanding of the pandemic, more complete knowledge of mental health, and better family and social relationship had less impact on their mental health. Therefore, to ensure a sound social support system, elaborate health instruction, and family communication and mutual understanding are conducive to alleviating the psychological stress caused by the epidemic, and it is positive for adolescent students to maintain a good mental health.