Noise Induced Depression-Like Behavior, Neuroinflammation and Synaptic Plasticity Impairments: The Protective Effects of Luteolin

Acute high-intensity noise exposure exacerbates anxiety-like behavior via neuroinflammation and blood brain barrier disruption of hippocampus in male rats

The health risks associated with acute noise exposure are increasing, particularly the risk of mental health. This study aims to identify the association between acute high-intensity noise exposure and anxiety behavior in male rats, and to explore the associated neurobiological mechanisms. Male rats were subjected to different levels of acute high-intensity noise to determine the intensity that causes long-lasting anxiety-like behaviors. Anxiety-like behaviors were evaluated using the open field test (OFT) and the elevated plus maze test (EPMT) on the third day and 1month post-exposure, respectively. A range of techniques, including immunofluorescence staining, western blot, ELISA, and real-time quantitative PCR, were used to investigate neuronal apoptosis, glial cell activation, neuroinflammation, and blood-brain barrier (BBB) disruption in the hippocampus. Upon exposure to 135 dB of acute noise, male rats exhibited enduring anxiety-like behaviors. Subsequent investigations discovered that this noise intensity not only activated glial cells and triggered neuroinflammation within the hippocampus but also decreased the expression levels of ZO-1, claudin-5, and occludin, suggesting a disruption of the BBB. Additionally, this exposure was associated with the induction of neuronal apoptosis in the hippocampal region. In conclusion, acute exposure to 135 dB noise may cause persistent anxiety in male rats through a cyclical interaction between neuroinflammation and BBB disruption, potentially leading to neuronal apoptosis.

Luteolin and its antidepressant properties: From mechanism of action to potential therapeutic application

Luteolin is a natural flavonoid compound exists in various fruits and vegetables. Recent studies have indicated that luteolin has variety pharmacological effects, including a wide range of antidepressant properties. Here, we systematically review the preclinical studies and limited clinical evidence on the antidepressant and neuroprotective effects of luteolin to fully explore its antidepressant power. Network pharmacology and molecular docking analyses contribute to a better understanding of the preclinical models of depression and antidepressant properties of luteolin. Seventeen preclinical studies were included that combined network pharmacology and molecular docking analyses to clarify the antidepressant mechanism of luteolin and its antidepressant targets. The antidepressant effects of luteolin may involve promoting intracellular noradrenaline (NE) uptake; inhibiting 5-hydroxytryptamine (5-HT) reuptake; upregulating the expression of synaptophysin, postsynaptic density protein 95, brain-derived neurotrophic factor, B cell lymphoma protein-2, superoxide dismutase, and glutathione S-transferase; and decreasing the expression of malondialdehyde, caspase-3, and amyloid-beta peptides. The antidepressant effects of luteolin are mediated by various mechanisms, including anti-oxidative stress, anti-apoptosis, anti-inflammation, anti-endoplasmic reticulum stress, dopamine transport, synaptic protection, hypothalamic-pituitary-adrenal axis regulation, and 5-HT metabolism. Additionally, we identified insulin-like growth factor 1 receptor (IGF1R), AKT serine/threonine kinase 1 (AKT1), prostaglandin-endoperoxide synthase 2 (PTGS2), estrogen receptor alpha (ESR1), and epidermal growth factor receptor (EGFR) as potential targets, luteolin has an ideal affinity for these targets, suggesting that it may play a positive role in depression through multiple targets, mechanisms, and pathways. However, the clinical efficacy of luteolin and its potential direct targets must be confirmed in further multicenter clinical case-control and molecular targeting studies.

Effects of Occupational Noise Exposure on Disease Control and Psychological Status in Patients with Diabetic Nephropathy

Objective To investigate the effects of occupational noise exposure on disease control and psychological status in patients with diabetic nephropathy.

METHODS

A cross-sectional study was conducted on 306 patients with diabetic nephropathy who visited the Second Affiliated Hospital of Fujian Medical University between January 2022 and January 2024. The patients were divided into two groups based on their occupational noise exposure level as follows: Group A (noise level ≥55 dB, 148 cases) and Group B (noise level <55 dB, 158 cases). The general information, noise exposure levels, glycaemic indicators [glycosylated haemoglobin (HbA1c), fasting plasma glucose (FPG), 2-hour postprandial plasma glucose (2hPG), glycated serum protein (GSP)], renal function indicators [blood urea nitrogen (BUN), urinary albumin excretion rate (UAER), serum creatinine (SCr), 24-hour urinary protein (24hUP)] and psychological status [Self-Rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS)] were compared between Groups A and B. Univariate analysis was performed using Pearson correlation analysis.

RESULTS

No significant differences were observed in age, gender and body mass index between the two groups (P > 0.05). However, glycaemic indicators such as HbA1c, FPG, PBG, GSP; renal function indicators such as BUN, UAER, SCr, 24hUP and psychological status (SAS and SDS scores) in Group A were significantly higher than those in Group B (P < 0.05). A significantly positive association was found between noise levels with SDS score (r = 0.321), FPG (r = 0.320) and UAER level (r = 0.405) (P < 0.001).

CONCLUSION

This study reveals that occupational noise exposure negatively impacts disease control and psychological status in patients with diabetic nephropathy. Therefore, focusing on noise control in clinical practice is essential.

Noise and mental health: evidence, mechanisms, and consequences

The recognition of noise exposure as a prominent environmental determinant of public health has grown substantially. While recent years have yielded a wealth of evidence linking environmental noise exposure primarily to cardiovascular ailments, our understanding of the detrimental effects of noise on the brain and mental health outcomes remains limited. Despite being a nascent research area, an increasing body of compelling research and conclusive findings confirms that exposure to noise, particularly from sources such as traffic, can potentially impact the central nervous system. These harms of noise increase the susceptibility to mental health conditions such as depression, anxiety, suicide, and behavioral problems in children and adolescents. From a mechanistic perspective, several investigations propose direct adverse phenotypic changes in brain tissue by noise (e.g. neuroinflammation, cerebral oxidative stress), in addition to feedback signaling by remote organ damage, dysregulated immune cells, and impaired circadian rhythms, which may collectively contribute to noise-dependent impairment of mental health. This concise review linking noise exposure to mental health outcomes seeks to fill research gaps by assessing current findings from studies involving both humans and animals.

Noise exposure-induced the cerebral alterations: From emerging evidence to antioxidant-mediated prevention and treatment

It's well acknowledged that noise exposure has become a major environmental risk factor of public health. The previous standpoint holds that the main harm of noise exposure is to cause hearing loss of human. However, in the past two decades a large number of studies have linked the noise exposure to various cerebral changes. In this review, we summarized that noise exposure led to cerebral changes through breaking the redox balance, inducing neuroinflammation and neuronal apoptosis and altering the neurotransmission in numerous brain areas, including cortex, thalamus, hippocampus, amygdala, striatum and cerebellum. Those cerebral changes finally result in a variety of disorders, such as tinnitus, anxiety, depression, cognitive impairment and motor dysfunction. Furthermore, we reviewed several antioxidants, such as resveratrol, vitamin C, curcumin, N-acetylcysteine and α-asarone, and highlighted their protective mechanisms against noise exposure, aiming to provide a promising strategy to prevent and treat noise exposure-induced diseases. Taken together, noise exposure induces various cerebral changes and further leads to disorders in the central nervous system, which can be ameliorated by the treatment with antioxidants.

The pharmacological actions of Danzhi-xiaoyao-San on depression involve lysophosphatidic acid and microbiota-gut-brain axis: novel insights from a systems pharmacology analysis of a double-blind, randomized, placebo-controlled clinical trial

Danzhi-xiaoyao-San (DZXYS), a Traditional Chinese Medicine, plays an essential role in the clinical treatment of depression, but its mechanisms in humans remain unclear. To investigate its pharmacological effects and mechanisms as an add-on therapy for depression, we conducted a double-blind, placebo-controlled trial with depressed patients receiving selective serotonin reuptake inhibitors (SSRIs). Serum and fecal samples were collected for metabolomic and microbiome analysis using UHPLC-QTRAP-MS/MS and 16S rRNA gene sequencing technologies, respectively. Depression symptoms were assessed using the 24-item Hamilton Depression Scale. We employed network pharmacology, metabolomics, and molecular docking to identify potential targets associated with DZXYS. We also examined the correlation between gut microbes and metabolites to understand how DZXYS affects the microbiota-gut-brain axis. The results showed that DZXYS combined with SSRIs was more effective than SSRIs alone in improving depression. We identified 39 differential metabolites associated with DZXYS treatment and found seven upregulated metabolic pathways. The active ingredients quercetin and luteolin were docked to targets (AVPR2, EGFR, F2, and CDK6) associated with the enriched pathways 'pancreatic cancer' and 'phospholipase D signaling pathway', which included the metabolite lysophosphatidic acid [LPA(0:0/16:0)]. Additionally, we identified 32 differential gut microbiota species related to DZXYS treatment, with Bacteroides coprophilus and Ruminococcus gnavus showing negative correlations with specific metabolites such as L-2-aminobutyric acid and LPA(0:0/16:0). Our findings indicate that DZXYS's antidepressant mechanisms involve multiple targets, pathways, and the regulation of LPA and the microbiota-gut-brain axis. These insights from our systems pharmacology analysis contribute to a better understanding of DZXYS's potential pharmacological mechanisms in depression treatment.Communicated by Ramaswamy H. Sarma.

The role of NLRP3 inflammasome-mediated neuroinflammation in chronic noise-induced impairment of learning and memory ability

BACKGROUND

Noise pollution pervades daily working and living environment, becoming a serious public health problem. In addition to causing auditory impairment, noise independently contributes to cognitive decline as a risk factor. Though neuroinflammation plays an important role in noise-induced cognitive deficits, the mechanisms underlying noise-induced neuroinflammation in the hippocampus are still poorly understood. Glial hyperactivation of the NLRP3 inflammasome contributes to various neurodegenerative diseases, including Alzheimer's disease (AD) and Parkinson's disease (PD). However, whether the NLRP3 inflammasome plays a role in noise-induced cognitive impairment remains to be further investigated.

METHODS

Adult male Wistar rats were exposed to 100 dB white noise (4 h/day) for 30 days with or without injection of the NLRP3 inhibitor MCC950 (10 mg/kg/day). The Morris water maze (MWM) test and the open field test (OFT) were performed to evaluate learning and memory ability of rats. HE staining was used to explore hippocampal pathological changes, while immunohistochemical staining was employed to evaluate the number and morphology of microglia and astrocytes. The mRNA levels of the NLRP3 inflammasome in the hippocampus were examined by Real-time PCR. The protein levels of NLRP3 inflammasome, inflammatory cytokines, p-Tau-S396, and amyloid-β (Aβ) 42 in the hippocampus were examined by Western blot. Immunofluorescence was used to observe the distribution of NLRP3 in glial cells and neurons, and the assembly of the NLRP3 inflammasome.

RESULTS

We found that noise exposure induced learning and memory impairment in rats, mainly related to the activation of microglia and astrocytes in hippocampus region. Noise exposure increased the protein levels of p-Tau-S396, Aβ42, ionized calcium binding adapter molecule 1 (Iba-1), glial fibrillary acidic protein (GFAP), interleukin (IL)-1β, IL-18, and tumor necrosis factor-α (TNF-α) in hippocampus. Furthermore, the hippocampus of noise-exposed rats showed elevated protein levels of NLRP3, ASC and cleaved caspase-1. The co-labeled immunofluorescence levels of Iba-1 or GFAP with NLRP3 significantly increased in the dentate gyrus (DG) region of the hippocampus. NLRP3 inhibitor MCC950 intervention reversed chronic noise-induced activation of NLRP3 inflammasome, AD-like pathologies and impairment of learning and memory in rats.

CONCLUSIONS

The NLRP3 inflammasome-mediated neuroinflammation played an essential role in chronic noise-induced cognitive dysfunction. These results provide novel strategies for the prevention and treatment of cognitive deficits caused by chronic noise.

Flavonoids against depression: a comprehensive review of literature

Background

Depression is a state of low mood and aversion to activity, which affects a person's thoughts, behavior, motivation, feelings, and sense of wellbeing. Pharmacologic therapies are still the best effective treatment of depression. Still, most antidepressant drugs have low efficacy and delayed onset of therapeutic action, have different side effects, and even exacerbate depression. Such conditions make it possible to look for alternatives. Consequently, we decided to summarize the impact of flavonoids on depression in this review.

Methods

We searched scientific databases such as SCOPUS, PubMed, and Google Scholar to find relevant studies until July 2022.

Results

A wide variety of natural components have been shown to alleviate depression, one of which is flavonoids. Due to the growing tendency to use natural antidepressant drugs, scientific studies are increasingly being conducted on flavonoids. This study aims to review the latest scientific researches that indicate the antidepressant potential of flavonoids. Various mechanisms include neurotransmitter system modulation and dopaminergic, noradrenergic, and serotonergic pathways regulation in the central nervous system. Different compounds of flavonoids have antidepressant properties in vivo or in vitro experiments or clinical trials and can be used as alternative and complementary treatments for depression. In general, it was observed that there were no severe side effects.

Conclusion

Our study proves the antidepressant potential of flavonoids, and considering the limited side effects, they can be used as complementary medicine for depressed patients.

Network pharmacology and experimental evidence: ERK/CREB/BDNF signaling pathway is involved in the antidepressive roles of Kaiyu Zhishen decoction

ETHNOPHARMACOLOGICAL RELEVANCE

Major Depressive Disorder (MDD) emerges as a complex psychosomatic condition, notable for its considerable suicidality and mortality rates. Increasing evidence suggests the efficacy of Chinese herbal medicine in mitigating depression symptoms and offsetting the adverse effects associated with conventional Western therapeutics. Notably, clinical trials have revealed the adjunctive antidepressant potential of Kaiyu Zhishen Decoction (KZD) alongside Western medication. However, the standalone antidepressant efficacy of KZD and its underlying mechanisms merit in-depth investigation.

AIM OF THE STUDY

This research aims to elucidate the impact of KZD on MDD and delineate its mechanistic pathways through integrated network pharmacological assessments and empirical in vitro and in vivo analyses.

MATERIALS AND METHODS

To ascertain the optimal antidepressant dosage and mechanism of KZD, a Chronic Unpredictable Mild Stress (CUMS)-induced depression model in mice was established to evaluate depressive behaviors. High-Performance Liquid Chromatography (HPLC) and network pharmacological approaches were employed to predict KZD's antidepressant mechanisms. Subsequently, hippocampal samples were subjected to 4D-DIA proteomic sequencing and validated through Western blot, immunofluorescence, Nissl staining, and pathway antagonist applications. Additionally, cortisol-stimulated PC12 cells were utilized to simulate neuronal damage, analyzing protein and mRNA levels of MAPK-related signals and cell proliferation markers.

RESULTS

The integration of network pharmacology and HPLC identified kaempferol and quercetin as KZD's principal active compounds for MDD treatment. Proteomic and network pharmacological KEGG pathway analyses indicated the MAPK signaling pathway as a critical regulatory mechanism for KZD's therapeutic effect on MDD. KZD was observed to mitigate CUMS-induced upregulation of p-ERK/ERK, CREB, and BDNF protein expressions in hippocampal cells by attenuating oxidative stress, thereby ameliorating neuronal damage and exerting antidepressant effects. The administration of PD98059 counteracted KZD's improvements in depression-like behaviors and downregulated p-ERK/ERK and BDNF protein expressions in the hippocampus.

CONCLUSIONS

This investigation corroborates KZD's pivotal, dose-dependent role in antidepressant activity. Both in vivo and in vitro experiments demonstrate KZD's capacity to modulate the ERK-CREB-BDNF signaling pathway by diminishing ROS expression induced by oxidative stress, enhancing neuronal repair, and thus, manifesting antidepressant properties. Accordingly, KZD represents a promising herbal candidate for further antidepressant research.

Association Between Perceived Noise Pollution and Sleep Quality: Findings from the 2018 Community Health Survey

OBJECTIVES

This study aimed to investigate the potential relationship between sleep quality and perceived noise.

METHODS

A cross-sectional study involving 185,246 adults (81,854 men and 103,392 women) participating in the 2018 Korea Community Health Survey (KCHS) was conducted. Subjective sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), while perceived noise pollutants were categorized into two groups: perceived noise pollution (n = 43,638) and perceived non-noise pollution (n = 141,608). We used chi-square tests and independent sample t tests to compare differences between the perceived noise group and the non-perceived noise group, as well as multivariate logistic regression analysis to calculate adjusted odds ratios (OR) for sleep quality variables.

RESULTS

The perceived noise pollution group had significantly poor psychosocial variables (stress, depression assessed by Patient health questionnaire-9 (PHQ-9)) than the perceived non-noise pollution group. Poor sleep quality (PSQI > 5) was associated with perceived noise pollution (OR 1.33, 95% confidence interval (CI) 1.30-1.36, P < 0.001). In addition, sleep quality (OR 1.09; 95% CI 1.06-1.13, P < 0.001); sleep latency (OR 1.11; 95% CI 1.09-1.14, P < 0.001); sleep duration (OR 1.10; 95% CI 1.07-1.13, P < 0.001); sleep efficiency (OR 1.20; 95% CI 1.16-1.25, P < 0.001); sleep disturbance (OR 1.46; 95% CI 1.42-1.51, P < 0.001); sleep medication use (OR 1.13; 95% CI 1.07-1.20, P = 0.002); and daytime dysfunction (OR 1.23; 95% CI 1.20-1.26, P < 0.001) were associated with perceived noise pollution after confounding variables.

CONCLUSION

Perceived noise pollution was significantly associated with poor sleep quality. Perceived noise annoyance could be used as a signal of health effects in the public community.

Effect of Music Therapy on the Psychological Well-Being of Maintenance Hemodialysis Patients: A Retrospective Study

OBJECTIVE

This study aimed to evaluate the management effect of music therapy on the psychological health of patients undergoing maintenance hemodialysis (MHD), with focus on improving levels of depression, anxiety and stress.

METHODS

A retrospective analysis of clinical data was conducted for 218 patients with sleep disorders accompanied by hemodialysis (HD) from January 2020 to December 2023. The subjects were categorized into a control group comprising 122 cases and an observational group comprising 96 cases. The observation group received music therapy in addition to routine management for 3 months. The psychological health status of patients was assessed using the Self-rating Depression Scale (SDS), Self-rating Anxiety Scale (SAS), and Hemodialysis Stressor Scale (HSS), among other indicators. t Tests, χ2 test and Wilcoxon test were performed.

RESULTS

After 3 months, the SDS and SAS scores of the observation group were significantly lower than those of the control group (P < 0.05). The scores for the "psychological stressors," "physiological stressors" and "social stressors" dimensions of HSS were also significantly lower in the observation group compared with those in the control group (P < 0.05). The overall satisfaction rate of the observation group was significantly higher than that of the control group (96.88% vs. 88.52%, P = 0.022).

CONCLUSION

Music therapy exerted a positive effect on improving the psychological health of HD patients, particularly in reducing stress levels. This study provides clinical evidence for music therapy as a low-cost and effective adjunctive treatment.

Luteolin alleviates depression-like behavior by modulating glycerophospholipid metabolism in the hippocampus and prefrontal cortex of LOD rats

BACKGROUND

Late-onset depression (LOD) is defined as primary depression that first manifests after the age of 65. Luteolin (LUT) is a natural flavonoid that has shown promising antidepressant effects and improvement in neurological function in previous studies.

AIMS

In this study, we utilized UPLC-MS/MS non-targeted metabolomics techniques, along with molecular docking technology and experimental validation, to explore the mechanism of LUT in treating LOD from a metabolomics perspective.

RESULTS

The behavioral results of our study demonstrate that LUT significantly ameliorated anxiety and depression-like behaviors while enhancing cognitive function in LOD rats. Metabolomic analysis revealed that the effects of LUT on LOD rats were primarily mediated through the glycerophospholipid metabolic pathway in the hippocampus and prefrontal cortex. The levels of key lipid metabolites, phosphatidylserine (PS), phosphatidylcholine (PC), and phosphatidylethanolamine (PE), in the glycerophospholipid metabolic pathway were significantly altered by LUT treatment, with PC and PE showing significant correlations with behavioral indices. Molecular docking analysis indicated that LUT had strong binding activity with phosphatidylserine synthase 1 (PTDSS1), phosphatidylserine synthase 2 (PTDSS2), and phosphatidylserine decarboxylase (PISD), which are involved in the transformation and synthesis of PC, PE, and PS. Lastly, our study explored the reasons for the opposing trends of PC, PE, and PS in the hippocampus and prefrontal cortex from the perspective of autophagy, which may be attributable to the bidirectional regulation of autophagy in distinct brain regions.

CONCLUSIONS

Our results revealed significant alterations in the glycerophospholipid metabolism pathways in both the hippocampus and prefrontal cortex of LOD rats. Moreover, LUT appears to regulate autophagy disorders by specifically modulating glycerophospholipid metabolism in different brain regions of LOD rats, consequently alleviating depression-like behavior in these animals.

Insights into the potential benefits of triphala polyphenols toward the promotion of resilience against stress-induced depression and cognitive impairment

In response to environmental challenges, stress is a common reaction, but dysregulation of the stress response can lead to neuropsychiatric disorders, including depression and cognitive impairment. Particularly, there is ample evidence that overexposure to mental stress can have lasting detrimental consequences for psychological health, cognitive function, and ultimately well-being. In fact, some individuals are resilient to the same stressor. A major benefit of enhancing stress resilience in at-risk groups is that it may help prevent the onset of stress-induced mental health problems. A potential therapeutic strategy for maintaining a healthy life is to address stress-induced health problems with botanicals or dietary supplements such as polyphenols. Triphala, also known as Zhe Busong decoction in Tibetan, is a well-recognized Ayurvedic polyherbal medicine comprising dried fruits from three different plant species. As a promising food-sourced phytotherapy, triphala polyphenols have been used throughout history to treat a variety of medical conditions, including brain health maintenance. Nevertheless, a comprehensive review is still lacking. Here, the primary objective of this review article is to provide an overview of the classification, safety, and pharmacokinetics of triphala polyphenols, as well as recommendations for the development of triphala polyphenols as a novel therapeutic strategy for promoting resilience in susceptible individuals. Additionally, we summarize recent advances demonstrating that triphala polyphenols are beneficial to cognitive and psychological resilience by regulating 5-hydroxytryptamine (5-HT) and brain-derived neurotrophic factor (BDNF) receptors, gut microbiota, and antioxidant-related signaling pathways. Overall, scientific exploration of triphala polyphenols is warranted to understand their therapeutic efficacy. In addition to providing novel insights into the mechanisms of triphala polyphenols for promoting stress resilience, blood brain barrier (BBB) permeability and systemic bioavailability of triphala polyphenols also need to be improved by the research community. Moreover, well-designed clinical trials are needed to increase the scientific validity of triphala polyphenols' beneficial effects for preventing and treating cognitive impairment and psychological dysfunction.