Antidepressant-Like Effect and Mechanism of Action of Honokiol on the Mouse Lipopolysaccharide (LPS) Depression Model

In Vitro and In Vivo Anti-Inflammatory and Antidepressant-like Effects of Cannabis sativa L. Extracts

Cannabis sativa L. has been widely used by humans for centuries for various purposes, such as industrial, ceremonial, medicinal, and food. The bioactive components of Cannabis sativa L. can be classified into two main groups: cannabinoids and terpenes. These bioactive components of Cannabis sativa L. leaf and inflorescence extracts were analyzed. Mice were systemically administered 30 mg/kg of Cannabis sativa L. leaf extract 1 h before lipopolysaccharide (LPS) administration, and behavioral tests were performed. We conducted an investigation into the oxygen saturation, oxygen tension, and degranulation of mast cells (MCs) in the deep cervical lymph nodes (DCLNs). To evaluate the anti-inflammatory effect of Cannabis sativa L. extracts in BV2 microglial cells, we assessed nitrite production and the expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α. The main bioactive components of the Cannabis sativa L. extracts were THCA (a cannabinoid) and β-caryophyllene (a terpene). Cannabis sativa L. leaf extract reduced the immobility time in the forced swimming test and increased sucrose preference in the LPS model, without affecting the total distance and time in the center in the open field test. Additionally, Cannabis sativa L. leaf extract improved oxygen levels and inhibited the degranulation of MCs in DCLNs. The Cannabis sativa L. extracts inhibited IL-1β, IL-6, TNF-α, nitrite, iNOS, and COX-2 expression in BV2 microglia cells. The efficacy of Cannabis sativa L. extracts was suggested to be due to the entourage effect of various bioactive phytochemicals. Our findings indicate that these extracts have the potential to be used as effective treatments for a variety of diseases associated with acute inflammatory responses.

Honokiol alleviates monosodium urate-induced gouty pain by inhibiting voltage-gated proton channels in mice

OBJECTIVE

To investigate whether honokiol (HNK) acted as an analgesic in connection with inhibiting the voltage-gated proton channel (Hv1).

METHODS

The model of gouty arthritis was induced by injecting monosodium urate (MSU) crystals into the hind ankle joint of mice. HNK was given by intragastric administration. Ankle swelling degree and mechanical allodynia were evaluated using ankle joint circumference measurement and von Frey filaments, respectively. Hv1 current, tail current, and action potential in dorsal root ganglion (DRG) neurons were recorded with patch-clamp techniques.

RESULTS

HNK (10, 20, 40 mg/kg) alleviated inflammatory response and mechanical allodynia in a dose-dependent manner. In normal DRG neurons, 50 µM Zn2+ or 2-GBI significantly inhibited the Hv1 current and the current density of Hv1 increased with increasing pH gradient. The amplitude of Hv1 current significantly increased on the 3rd after MSU treatment, and HNK dose-dependently reversed the upregulation of Hv1 current. Compared with MSU group, 40 mg/kg HNK shifted the activation curve to the direction of more positive voltage and increased reversal potential to the normal level. In addition, 40 mg/kg HNK reversed the down-regulation of tail current deactivation time constant (τtail) but did not alter the neuronal excitability of DRG neurons in gouty mice.

CONCLUSION

HNK may be a potential analgesic by inhibiting Hv1 current.

Honokiol Prevents Intestinal Barrier Dysfunction in Mice with Severe Acute Pancreatitis and Inhibits JAK/STAT1 Pathway and Acetylation of HMGB1

OBJECTIVE

To investigate the effect of honokiol (HON) and the role of high-mobility group protein B1 (HMGB1) on the pathogenesis of severe acute pancreatitis (SAP).

METHODS

Thirty mice were numbered according to weight, and randomly divided into 5 groups using a random number table, including control, SAP, SAP and normal saline (SAP+NS), SAP and ethyl pyruvate (SAP+EP), or SAP+HON groups, 6 mice in each group. Samples of pancreas, intestine, and blood were collected 12 h after SAP model induction for examination of pathologic changes, immune function alterations by enzyme linked immunosorbent assay (ELISA), and Western blot. In vitro experiments, macrophages were divided into 5 groups, the control, lipopolysaccharide (LPS), LPS+DMSO (DMSO), LPS+anti-HMGB1 monoclonal antibody (mAb), and LPS+ HON groups. The tight connection level was determined by transmission electron microscopy and fluorescein isothiocyanate-labeled. The location and acetylation of HMGB1 were measured by Western blot. Finally, pyridone 6 and silencing signal transducer and activator of the transcription 1 (siSTAT1) combined with honokiol were added to determine whether the Janus kinase (JAK)/ STAT1 participated in the regulation of honokiol on HMGB1. The protein expression levels of HMGB1, JAK, and STAT1 were detected using Western blot.

RESULTS

Mice with SAP had inflammatory injury in the pancreas, bleeding of intestinal tissues, and cells with disrupted histology. Mice in the SAP+HON group had significantly fewer pathological changes. Mice with SAP also had significant increases in the serum levels of amylase, lipase, HMGB1, tumor necrosis factor- α, interleukin-6, diamine oxidase, endotoxin-1, and procalcitonin. Mice in the SAP+HON group did not show these abnormalities (P<0.01). Studies of Caco-2 cells indicated that LPS increased the levels of occludin and claudin-1 as well as tight junction permeability, decreased the levels of junctional adhesion molecule C, and elevated intercellular permeability (P<0.01). HON treatment blocked these effects. Studies of macrophages indicated that LPS led to low nuclear levels of HMGB1, however, HON treatment increased the nuclear level of HMGB1 (P<0.01). HON treatment also inhibited the expressions of JAK1, JAK2, and STAT1 (P<0.01) and increased the acetylation of HMGB1 (P<0.05).

CONCLUSION

HON prevented intestinal barrier dysfunction in SAP by inhibiting HMGB1 acetylation and JAK/STAT1 pathway.

Chronic Stress-Induced Neuroinflammation: Relevance of Rodent Models to Human Disease

The brain is the central organ of adaptation to stress because it perceives and determines threats that induce behavioral, physiological, and molecular responses. In humans, chronic stress manifests as an enduring consistent feeling of pressure and being overwhelmed for an extended duration. This can result in a persistent proinflammatory response in the peripheral and central nervous system (CNS), resulting in cellular, physiological, and behavioral effects. Compounding stressors may increase the risk of chronic-stress-induced inflammation, which can yield serious health consequences, including mental health disorders. This review summarizes the current knowledge surrounding the neuroinflammatory response in rodent models of chronic stress-a relationship that is continually being defined. Many studies investigating the effects of chronic stress on neuroinflammation in rodent models have identified significant changes in inflammatory modulators, including nuclear factor-κB (NF-κB) and toll-like receptors (TLRs), and cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, and IL-6. This suggests that these are key inflammatory factors in the chronic stress response, which may contribute to the establishment of anxiety and depression-like symptoms. The behavioral and neurological effects of modulating inflammatory factors through gene knockdown (KD) and knockout (KO), and conventional and alternative medicine approaches, are discussed.

Beneficial effect of honokiol and magnolol on polyol pathway and oxidative stress parameters in the testes of diabetic rats

In diabetes hyperglycemia, excessive production of free radicals and present oxidative stress lead to many complications in the body, including male reproductive system disorders. To prevent the development of diabetic complications in the testes resulting from them, it seems beneficial to include compounds considered as natural antioxidants. Honokiol and magnolol are neolignans obtained from magnolia bark, which possess proven antioxidant properties. The aim of this study was to evaluate the effect of honokiol and magnolol on the parameters of oxidative stress, polyol pathway and glycation products in the testes as well as on selected biochemical parameters in the blood serum of rats with type 2 diabetes. The study was conducted on mature male Wistar rats with high fat diet and streptozotocin-induced type 2 diabetes. Neolignans-treated rats received honokiol or magnolol orally at the doses of 5 or 25 mg/kg, respectively, for 4 weeks. Parameters related to glucose and lipid homeostasis, basic serological parameters and sex hormones level in the serum as well as polyol pathway parameters, antioxidant enzyme activity, endogenous antioxidants level, sumaric parameters for oxidative stress and oxidative damage in the testes were estimated. Oral administration of honokiol and magnolol turned out to be beneficial in combating the effects of oxidative stess in the testes, but showed no favorable effects on serum biochemical parameters. Additionally, magnolol compared to honokiol revealed more advantageous impact indicating the reversal of the effects of diabetic complications in the male reproductive system and counteracted oxidative stress damages and polyol pathway disorders in the testes.

rTMS reduces spatial learning and memory deficits induced by sleep deprivation possibly via suppressing the expression of kynurenine 3-monooxygenase in rats

INTRODUCTION

Impairment of learning and memory caused by sleep deprivation is a common symptom that significantly affects quality of life. Repetitive transcranial magnetic stimulation (rTMS) is a promising approach to exert a positive effect on cognitive impairment. However, there is less known about the mechanism of rTMS for learning and memory induced by chronic REM sleep deprivation (CRSD). This study was to detect the effects of rTMS on spatial learning and memory deficits by CRSD and explore possible mechanism.

METHODS

Sixty male Sprague-Dawley rats were randomly divided into four groups: wide platform (Control), sleep deprivation (SD), sleep deprivation + rTMS (TMS), and sleep deprivation + sham rTMS (Sham-TMS). Morris water maze (MWM) and open field test (OFT) assessed spatial learning and memory and anxiety of rats with pre/post-intervention. Golgi staining and transmission electron microscope (TEM) were used to observe structural variations of synapses in the hippocampus. The alteration in gene expression of different groups was analyzed by RNA-sequencing (RNA-Seq), and the key gene was screened and identified by quantitative polymerase chain reaction (qPCR) and subsequently verified with western blotting and immunofluorescence.

RESULTS

The behavioral test showed spatial learning and memory decreased and anxiety increased in the SD group compared to the Control and TMS groups. Moreover, rTMS improved spine density, ultrastructural damage, and quantities of synapses. In accordance with RNA-Seq, 56 differentially expressed genes (DEGs) were identified by comparing alternations in four groups and concentrated on kynurenine 3-monooxygenase (KMO). The expression of KMO increased significantly in rats of the SD group compared to the Control and TMS groups identified by qPCR, western blotting, and immunofluorescence.

CONCLUSION

1 Hz rTMS alleviated spatial learning and memory deficits induced by CRSD probably via down-regulating the expression of KMO and improving the structure and quantity of synapses in the hippocampus of rats.

CircDYM attenuates microglial apoptosis via CEBPB/ZC3H4 axis in LPS-induced mouse model of depression

Major depressive disorder (MDD) is a highly prevalent condition and one of the most common psychiatric disorders worldwide. Circular RNA (circRNA) has been increasingly implicated in MDD. However, a comprehensive understanding of circRNA and microglial apoptosis in depression is incomplete. Here, we show that circDYM inhibits microglial apoptosis induced by LPS via CEBPB/ZC3H4 axis. CircDYM prevents the translocation of CEBPB from cytoplasm to the nucleus by binding with CEBPB. Moreover, LPS-induced CEBPB nuclear entry downregulates the expression of ZC3H4, in which promotes autophagy and apoptosis in microglia. Taken together, our findings provide new insights into the relationship between circDYM and microglial apoptosis and shed new light on the function of this novel mechanism in depression-associated complex changes in the brain.

Feasibility of applying a noninvasive method for sleep monitoring based on mouse behaviors

INTRODUCTION

Currently, electroencephalogram (EEG)/electromyogram (EMG) system is widely regarded as the "golden standard" for sleep monitoring. Imperfectly, its invasive monitoring may somehow interfere with the natural state of sleep. Up to now, noninvasive methods for sleep monitoring have developed, which could preserve the undisturbed and naïve sleep state of mice to the greatest extent, but the feasibility of their application under different conditions should be extensive validated.

METHODS

Based on existing research, we verified the feasibility of a sleep monitoring system based on mouse behaviors under different conditions. The experimental mice were exposed to various stresses and placed into a combined device comprising noninvasive sleep monitoring equipment and an EEG/EMG system, and the sleep status was recorded under different physiological, pharmacological, and pathophysiological conditions. The consistency of the parameters obtained from the different systems was calculated using the Bland-Altman statistical method.

RESULTS

The results demonstrated that the physiological sleep times determined by noninvasive sleep monitoring system were highly consistent with those obtained from the EEG/EMG system, and the coefficients were 94.4% and 95.1% in C57BL/6J and CD-1 mice, respectively. The noninvasive sleep monitoring system exhibited high sensitivity under the sleep-promoting effect of diazepam and caffeine-induced wakefulness, which was indicated by its ability to detect the effect of dosage on sleep times, and accurate determination of the sleep/wakeful status of mice under different pathophysiological conditions. After combining the data obtained from all the mice, the coefficient between the sleep times detected by behavior-based sleep monitoring system and those obtained from the EEG/EMG equipment was determined to .94.

CONCLUSION

The results suggested that behavior-based sleep monitoring system could accurately evaluate the sleep/wakeful states of mice under different conditions.

Neuropharmacological potential of honokiol and its derivatives from Chinese herb Magnolia species: understandings from therapeutic viewpoint

Honokiol is a neolignan biphenol found in aerial parts of the Magnolia plant species. The Magnolia plant species traditionally belong to China and have been used for centuries to treat many pathological conditions. Honokiol mitigates the severity of several pathological conditions and has the potential to work as an anti-inflammatory, anti-angiogenic, anticancer, antioxidant, and neurotherapeutic agent. It has a long history of being employed in the healthcare practices of Southeast Asia, but in recent years, a greater scope of research has been conducted on it. Plenty of experimental evidence suggests it could be beneficial as a neuroprotective bioactive molecule. Honokiol has several pharmacological effects, leading to its exploration as a potential therapy for neurological diseases (NDs), including Alzheimer's disease (AD), Parkinson's disease (PD), cerebral ischemia, anxiety, depression, spinal cord injury, and so on. So, based on the previous experimentation reports, our goal is to discuss the neuroprotective properties of honokiol. Besides, honokiol derivatives have been highlighted recently as possible therapeutic options for NDs. So, this review focuses on honokiol's neurotherapeutic actions and toxicological profile to determine their safety and potential use in neurotherapeutics.

Saffron extract interferes with lipopolysaccharide-induced brain activation of the kynurenine pathway and impairment of monoamine neurotransmission in mice

Background

Although activation of inflammatory processes is essential to fight infections, its prolonged impact on brain function is well known to contribute to the pathophysiology of many medical conditions, including neuropsychiatric disorders. Therefore, identifying novel strategies to selectively counter the harmful effects of neuroinflammation appears as a major health concern. In that context, this study aimed to test the relevance of a nutritional intervention with saffron, a spice known for centuries for its beneficial effect on health.

Methods

For this purpose, the impact of an acute oral administration of a standardized saffron extract, which was previously shown to display neuromodulatory properties and reduce depressive-like behavior, was measured in mice challenged with lipopolysaccharide (LPS, 830 μg/kg, ip).

Results

Pretreatment with saffron extract (6.5 mg/kg, per os) did not reduce LPS-induced sickness behavior, preserving therefore this adaptive behavioral response essential for host defense. However, it interfered with delayed changes of expression of cytokines, chemokines and markers of microglial activation measured 24 h post-LPS treatment in key brain areas for behavior and mood control (frontal cortex, hippocampus, striatum). Importantly, this pretreatment also counteracted by that time the impact of LPS on several neurobiological processes contributing to inflammation-induced emotional alterations, in particular the activation of the kynurenine pathway, assessed through the expression of its main enzymes, as well as concomitant impairment of serotonergic and dopaminergic neurotransmission.

Conclusion

Altogether, this study provides important clues on how saffron extract interferes with brain function in conditions of immune stimulation and supports the relevance of saffron-based nutritional interventions to improve the management of inflammation-related comorbidities.

Natural antioxidant formula ameliorates lipopolysaccharide-induced impairment of hippocampal neurogenesis and contextual fear memory through suppression of neuroinflammation in rats

This study investigated the ameliorating effects of a natural antioxidant formula (NAF) consisting of Ginkgo biloba leaf extract, docosahexaenoic acid/eicosapentaenoic acid, ferulic acid, flaxseed oil, vitamin E, and vitamin B12 on a lipopolysaccharide (LPS)-induced cognitive dysfunction model in rats. Six-week-old rats received a diet containing 0.5% (w/w) NAF for 38 days from Day 1, and LPS (1 mg/kg body weight) was administered intraperitoneally once daily on Days 8 and 10. On Day 11, LPS alone increased interleukin-1β and tumor necrosis factor-α in the hippocampus and cerebral cortex and the numbers of M1-type microglia/macrophages and GFAP+ reactive astrocytes in the hilus of the hippocampal dentate gyrus. NAF treatment decreased brain proinflammatory cytokine levels and increased the number of M2-type microglia/macrophages. During Days 34-38, LPS alone impaired fear memory acquisition and the extinction learning process, and NAF facilitated fear extinction learning. On Day 38, LPS alone decreased the number of type-3 neural progenitor cells in the hippocampal neurogenic niche, and NAF restored the number of type-3 neural progenitor cells and increased the numbers of both immature granule cells in the neurogenic niche and reelin+ hilar interneurons. Thus, NAF exhibited anti-inflammatory effects and ameliorated LPS-induced adverse effects on hippocampal neurogenesis and fear memory learning, possibly through amplification of reelin signaling by hilar interneurons. These results suggest that neuroinflammation is a key factor in the development of LPS-induced impairment of fear memory learning, and supplementation with NAF in the present study helped to prevent hippocampal neurogenesis and disruptive neurobehaviors caused by neuroinflammation.

Affinity character analysis of magnolol and honokiol based on stepwise frontal analysis coupled with cell membrane chromatography

Magnolol and honokiol have been reported to exhibit anti-cancer activity. However, few studies are in relation to the interaction of magnolol/honokiol with vascular endothelial growth factor 2 (VEGFR2). In this study, a membrane chromatography method based on VEGFR2 was established for the interaction characteristic analysis between drug and receptor. The selectivity, repeatability and stability of the chromatographic model were evaluated using drugs acting on different receptors. The affinity between VEGFR2 and magnolol/honokiol was verified by cell membrane chromatography. The binding sites of magnolol/honokiol and VEGFR2 were analyzed by zonal elution. Especially, the dissociation equilibrium constants (Kd) of magnolol/honokiol and VEGFR2 were measured by zonal elution and stepwise frontal analysis respectively. In addition, the actions of magnolol/honokiol on VEGFR2 were analyzed by stepwise frontal analysis at different temperatures. The results showed that the binding sites of magnolol and honokiol on VEGFR2 were different from sorafenib, indicating that magnolol and honokiol could be used as competitive agents for self-competitive displacement experiment. The Kd values (order of magnitude) of magnolol/honokiol with VEGFR2 measured by stepwise frontal analysis were consistent with the zonal elution results. Honokiol binds VEGFR2 with higher affinity than magnolol. The main forces that stabilize the interactions of honokiol with VEGFR2 are hydrogen bonds and van der Waal's forces, and the main force of magnolol is electrostatic forces. These discoveries could assist in the prediction of drug activity and understanding for the underlying mechanism.

Gypenoside-14 Reduces Depression via Downregulation of the Nuclear Factor Kappa B (NF-kB) Signaling Pathway on the Lipopolysaccharide (LPS)-Induced Depression Model

Neuroinflammation is a common pathogenetic sign of depression and is closely linked to the development of depression. Many clinical anti-inflammatory drugs act as antidepressants by reducing the neuroinflammatory response. Previous research found that gypenosides and their bioactive compound gypenoside-14 (GP-14) had neuroprotective effects against hypoxia-induced injury and reduced neuroinflammation-related high-altitude cerebral edema. Here we investigated the effects of GP-14 on the lipopolysaccharide (LPS)-induced depression-like behavior model. LPS (0.5 mg/kg) was injected into mice intraperitoneally for 7 consecutive days to induce depression-like behavior, which is considered a model for the exacerbation of depression. GP-14 in the amount of 100 mg/kg was simultaneously administered by gavage for 7 days. In the LPS-induced depression model, GP-14 not only attenuated depression-like behavior but also improved the anxiety-like behavior of the mice. Additionally, GP-14 treatment mitigated learning and cognitive decline in depressed mice. ELISA and immunofluorescence staining results revealed that GP-14 inhibited the upregulation of pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6), and suppressed the activation of astrocytes induced with LPS, indicating its potent anti-inflammatory effect. GP-14 pretreatment in C8 cells and primary astrocytes can inhibit the activation of the NF-κB signaling pathway and downregulate the levels of pro-inflammatory factors. In summary, our findings showed that GP-14 had significant anti-inflammation and anti-depression properties; thus, GP-14 could be a promising lead compound for treating depression.

Inulin-type oligosaccharides of Morinda officinalis exerted antidepressant effects by reducing hippocampal inflammation

Neuroinflammation contributes to the pathogenesis of depression. Inulin-type oligosaccharides of Morinda officinalis (IOMO) exert antidepressant-like effects in rodents and patients with depression, while the underlying mechanisms remain unclear. This study used chronic restraint stress (CRS) and lipopolysaccharide (LPS) to induce depression-like behaviors in mice. Western blotting and ELISA analysis were used to investigate the effects of IOMO on inflammatory cytokine levels. Immunofluorescence analysis was used to investigate the effects of IOMO on hippocampal NLRP3 inflammasome and microglial cells. The results suggested that 6 weeks of CRS induced significant depression-like behaviors based on the sucrose preference test (SPT), tail suspension test (TST), and forced swimming test (FST), which were accompanied by increases in the expression of IL-6 and the activation of hippocampal microglial cells. Chronic treatment with IOMO (25 mg/kg, i.g.) for 28 days significantly reversed these depression-like behaviors and inhibited the activation of microglial cells. Furthermore, LPS (0.5 mg/kg, i.p.) also significantly induced depression-like behaviors in the TST, FST, and novelty-suppressed feeding test (NSFT), as well as increased the expression of IL-1β and caspase-1, and activated the microglial cells and the NLRP3 inflammasome in the hippocampus. Treatment with IOMO for 9 days significantly reversed these depression-like behaviors and normalized the LPS-induced activation of the microglial cells and NLRP3 inflammasome. Taken together, these results suggested that IOMO exerted antidepressant-like effects via hippocampal microglial NLRP3 inflammasome mediation followed by caspase-1 inhibition and the production of IL-1β. These findings provide a basis for developing new antidepressants targeting the microglial NLRP3 inflammasome.

Gasdermin D Plays an Oncogenic Role in Glioma and Correlates to an Immunosuppressive Microenvironment

BACKGROUND

Understanding the molecular mechanisms driving oncogenic processes in glioma is important in order to develop efficient treatments. Recent studies have proposed gasdermin D (GSDMD) as a newly discovered pyroptosis executive protein associated with tumorigenesis. However, the precise effect of GSDMD on glioma progression remains unknown.

METHODS

The expression levels of GSDMD in 931 glioma and 1157 normal control tissues were collected. A series of bioinformatic approaches and in vivo and in vitro experiments were used to investigate the roles and mechanisms of GDSMD in glioma.

RESULTS

Significant upregulation of GSDMD was detected in glioma tissues compared to normal brain tissues. Patients with glioma and higher GSDMD levels had shorter overall survival, and the Cox regression analysis revealed that GSDMD was an independent risk factor. In addition, upregulation of GSDMD was associated with higher tumor mutation burden and PD-1/PD-L1 expression. Immune infiltration and single-cell analyses indicated that GSDMD was positively associated with an immunosuppressive microenvironment with more infiltrated macrophages and cancer-associated fibroblasts. Furthermore, the in vitro and in vivo experiments revealed that GSDMD knockdown inhibited glioma proliferation, migration, and growth in vivo.

CONCLUSION

Our analyses revealed a relatively comprehensive understanding of the oncogenic role of GSDMD in glioma. GSDMD is a promising prognostic biomarker and a potential target for glioma treatment.

Efficacy and safety of Banxia-Houpo-Tang (Banha-Hubak-Tang) for depression: A systematic review and meta-analysis

BACKGROUND

and purpose: Banxia-Houpo-Tang (Banha-Hubak-Tang, BHT) is an East Asian traditional herbal medicine used for treating depression. Hence, this review aimed to provide reliable evidence on the efficacy and safety of BHT for depression.

METHODS

Overall, 15 electronic databases were searched until July 31, 2022, and randomized controlled trials (RCTs) of BHT for depression were reviewed. The cochrane risk of bias tool version 2.0 was used for quality assessment. A meta-analysis was conducted to evaluate the efficacy and safety of BHT for depression.

RESULTS

Fifteen RCTs (1,714 participants) were included. The pooled results suggested that the efficacy of BHT alone (standardized mean difference [SMD], -0.39; 95% confidence interval [CI], -0.79 to 0.00; P = 0.05) was similar to that of antidepressants alone in terms of the Hamilton depression scale (HAMD) scores. Their combination led to a more significant improvement in HAMD scores (SMD, -0.91; 95% CI, -1.21 to 0.60; P < 0.00001). Moreover, compared with antidepressants alone, BHT alone had a lower risk of causing adverse events, but the combination therapy exhibited a similar risk. No severe adverse events were reported. The overall risk of bias was high. The quality of evidence was very low to moderate.

CONCLUSION

The study results indicate that BHT may be beneficial for treating depression. However, due to the clinical heterogeneity and low methodological quality of the included studies, the obtained findings should be interpreted with caution. Hence, further studies on this topic are warranted.

Polyphenols as novel interventions for depression: exploring the efficacy, mechanisms of action, and implications for future research

Numerous animal and human studies have assessed the relationship between polyphenols and outcomes related to depression. However, no comprehensive synthesis of the main findings has been conducted. The aim of this manuscript was to systematically review the available evidence from animal and human studies on the association and the effects of dietary polyphenols on depression and provide recommendations for future research. We based our review on 163 preclinical animal, 16 observational and 44 intervention articles assessing the relationship between polyphenols and outcomes related to depression. Most animal studies demonstrated that exposure to polyphenols alleviated behaviours reported to be associated with depression. However, human studies are less clear, with some studies reporting and inverse relationship between the intake of some polyphenols, and polyphenol rich foods and depression risk and symptoms, while others reporting no association or effect. Hence, while there has been extensive research conducted in animals and there is some supporting evidence in humans, further human studies are required, particularly in younger and clinical populations.

IDO/Kynurenine; novel insight for treatment of inflammatory diseases

Inflammation and oxidative stress play pivotal roles in pathogenesis of many diseases including cancer, type 2 diabetes, cardiovascular disease, atherosclerosis, neurological diseases, and inflammatory diseases such as inflammatory bowel disease (IBD). Inflammatory mediators such as interleukins (ILs), interferons (INF-s), and tumor necrosis factor (TNF)-α are related to an extended chance of inflammatory diseases initiation or progression due to the over expression of the nuclear factor Kappa B (NF-κB), signal transducer of activators of transcription (STAT), nod-like receptor family protein 3 (NLRP), toll-like receptors (TLR), mitogen-activated protein kinase (MAPK), and mammalian target of rapamycin (mTOR) pathways. These pathways are completely interconnected. Theindoleamine 2,3 dioxygenase (IDO) subset of the kynurenine (KYN) (IDO/KYN), is a metabolic inflammatory pathway involved in production of nicotinamide adenine dinucleotide (NAD + ). It has been shown that IDO/KYN actively participates in inflammatory processes and can increase the secretion of cytokines that provoke inflammatory diseases. Data were extracted from clinical and animal studies published in English between 1990-April 2022, which were collected from PubMed, Google Scholar, Scopus, and Cochrane library. IDO/KYN is completely associated with inflammatory-related pathways, thus leading to the production of cytokines such as TNF-α, IL-1β, and IL-6, and ultimately development and progression of various inflammatory disorders. Inhibition of the IDO/KYN pathway might be a novel therapeutic option for inflammatory diseases. Herein, we gathered data on probable interactions of the IDO/KYN pathway with induction of some inflammatory diseases.

Synthesis, Quality Control and Preliminary Activity Evaluation of a New Compound HM475

Based on the principle of molecular splicing and theory of traditional Chinese medicine pairs, a new multi-active compound (HM475) was synthesized by connecting metformin with honokiol, and its structure was characterized, which not only reduced the toxicity of raw materials, but also maintained the original activity, and had a certain significance in research and innovation. At the same time, quality control and preliminary activity evaluation were carried out, and the effect of HM475 on neuroinflammation was further explored, which provided a new idea for drug development of neurodegenerative diseases.

Honokiol attenuates mitochondrial fission and cell apoptosis by activating Sirt3 in intracerebral hemorrhage

BACKGROUND

Sirtuin-3 (Sirt3) has been documented to protect against mitochondrial dysfunction and apoptosis. Honokiol (HKL) is a Sirt3 pharmacological activator with reported neuroprotective effects in multiple neurological disorders. The present study aimed to explore the neuroprotective effects of HKL and the role of Sirt3 following intracerebral hemorrhage (ICH).

METHODS

An in vivo ICH model in rats was established by injecting autologous blood into the right basal ganglia. PC12 cells were stimulated with hemin. For the in vivo investigation, the modified Neurological Severity Scores and the Morris water maze test were performed to assess neurological deficits. Hematoxylin-Eosin and Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining were employed to evaluate the histopathology and apoptosis. Immunohistochemical staining was used to investigate the expression of Sirt3. Adenosine triphosphate (ATP) levels were quantified to assess mitochondrial dysfunction. Cell counting kit-8, lactate dehydrogenase assay, and flow cytometry were used to analyze cell vitality and apoptosis in vitro. Immunofluorescence staining was performed to observe mitochondrial morphology and dynamin-related protein 1 (Drp1) localization to mitochondria. Western blot was applied to quantify the expression of Sirt3, Bax, Bcl-2, cleaved-caspase-3, Drp1, phosphorylation of Drp1 at serine-616, and phosphorylation of Drp1 at serine-637 in vivo and in vitro.

RESULTS

HKL treatment alleviated neurological deficits, attenuated the histopathological damage and cell apoptosis, and restored the decreased ATP levels in ICH rats. HKL improved cell survival rate, reduced cell apoptosis, and inhibited mitochondrial fission in PC12 cells. Moreover, both in vivo and in vitro models showed increased phosphorylation of Drp1 at Ser616, and reduced phosphorylation of Drp1 at Ser637. Meanwhile, immunofluorescence co-localization analysis revealed that hemin increased the overlap of Drp1 and mitochondria in PC12 cells. The phosphorylation and mitochondrial translocation of Drp1 were effectively reversed by HKL treatment. Importantly, the selective Sirt3 inhibitor 3-(1H-1,2,3-triazol-4-yl) pyridine suppressed these effects.

CONCLUSION

Our findings demonstrated that HKL ameliorated ICH-induced apoptosis and mitochondrial fission by Sirt3, suggesting that HKL has immense prospects for the treatment of ICH.

Roxadustat (FG-4592) abated lipopolysaccharides-induced depressive-like symptoms via PI3K signaling

Background

Despite its role in inflammation and the redox system under hypoxia, the effects and molecular mechanisms of hypoxia-inducible factor (HIF) in neuroinflammation-associated depression are poorly explored. Furthermore, Prolyl hydroxylase domain-containing proteins (PHDs) regulate HIF-1; however, whether and how PHDs regulate depressive-like behaviors under Lipopolysaccharides (LPS)-induced stress conditions remain covered.

Methods

To highlight the roles and underlying mechanisms of PHDs-HIF-1 in depression, we employed behavioral, pharmacological, and biochemical analyses using the LPS-induced depression model.

Results

Lipopolysaccharides treatment induced depressive-like behaviors, as we found, increased immobility and decreased sucrose preference in the mice. Concurrently, we examined increased cytokine levels, HIF-1 expression, mRNA levels of PHD1/PHD2, and neuroinflammation upon LPS administration, which Roxadustat reduced. Furthermore, the PI3K inhibitor wortmannin reversed Roxadustat-induced changes. Additionally, Roxadustat treatment attenuated LPS-induced synaptic impairment and improved spine numbers, ameliorated by wortmannin.

Conclusion

Lipopolysaccharides-dysregulates HIF-PHDs signaling may contribute to neuroinflammation-coincides depression via PI3K signaling.

Gut microbiota: A new target for traditional Chinese medicine in the treatment of depression

ETHNIC PHARMACOLOGICAL RELEVANCE

The causes of depression are complex. Many factors are involved in its pathogenesis, including the individual's biological and social environment. Although numerous studies have reported that the gut microbiota plays a significant role in depression, drugs that regulate the gut microbiota to treat depression have not yet been comprehensively reviewed. At the same time, more and more attention has been paid to the characteristics of traditional Chinese medicine (TCM) in improving depression by regulating gut microbiota. In ancient times, fecal microbiota transplantation was recorded in TCM for the treatment of severe diseases. There are also records in Chinese ancient books about the use of TCM to adjust gut microbiota to treat diseases, which has opened up a unique research field in TCM. Therefore, this article focuses on the pharmacological effects, targets, and mechanisms of TCM in improving depression by mediating the influence of gut microbiota.

AIM OF THIS REVIEW

To summarize the role the gut microbiota plays in depression, highlight potential regulatory targets, and elucidate the anti-depression mechanisms of TCMs through regulation of the gut microbiota.

METHODS

A systematic review of 256 clinical trials and pharmaceutical studies published until June 2022 was conducted in eight electronic databases (Web of Science, PubMed, SciFinder, Research Gate, ScienceDirect, Google Scholar, Scopus, and China Knowledge Infrastructure), according to the implemented PRISMA criteria, using the search terms "traditional Chinese medicine," "depression," and "gut microbiota."

RESULTS

Numerous studies reported the effects of different gut bacteria on depression and that antidepressants work through the gut microbiota. TCM preparations based on compound Chinese medicine, the Chinese Materia Medica, and major bioactive components exerted antidepressant-like effects by improving levels of neurotransmitters, short-chain fatty acids, brain-derived neurotrophic factor, kynurenine, and cytokines via regulation of the gut microbiota.

CONCLUSION

This review summarized the anti-depression effects of TCM on the gut microbiota, providing evidence that TCMs are safe and effective in the treatment of depression and may provide a new therapeutic approach.

Depression and Its Phytopharmacotherapy-A Narrative Review

Depression is a mental health disorder that develops as a result of complex psycho-neuro-immuno-endocrinological disturbances. This disease presents with mood disturbances, persistent sadness, loss of interest and impaired cognition, which causes distress to the patient and significantly affects the ability to function and have a satisfying family, social and professional life. Depression requires comprehensive management, including pharmacological treatment. Because pharmacotherapy of depression is a long-term process associated with the risk of numerous adverse drug effects, much attention is paid to alternative therapy methods, including phytopharmacotherapy, especially in treating mild or moderate depression. Preclinical studies and previous clinical studies confirm the antidepressant activity of active compounds in plants, such as St. John's wort, saffron crocus, lemon balm and lavender, or less known in European ethnopharmacology, roseroot, ginkgo, Korean ginseng, borage, brahmi, mimosa tree and magnolia bark. The active compounds in these plants exert antidepressive effects in similar mechanisms to those found in synthetic antidepressants. The description of phytopharmacodynamics includes inhibiting monoamine reuptake and monoamine oxidase activity and complex, agonistic or antagonistic effects on multiple central nervous system (CNS) receptors. Moreover, it is noteworthy that the anti-inflammatory effect is also important to the antidepressant activity of the plants mentioned above in light of the hypothesis that immunological disorders of the CNS are a significant pathogenetic factor of depression. This narrative review results from a traditional, non-systematic literature review. It briefly discusses the pathophysiology, symptomatology and treatment of depression, with a particular focus on the role of phytopharmacology in its treatment. It provides the mechanisms of action revealed in experimental studies of active ingredients isolated from herbal antidepressants and presents the results of selected clinical studies confirming their antidepressant effectiveness.

Role of the Intestinal Microbiota in the Genesis of Major Depression and the Response to Antidepressant Drug Therapy: A Narrative Review

A major depressive disorder is a serious mental illness characterized by a pervasive low mood that negatively concerns personal life, work life, or education, affecting millions of people worldwide. To date, due to the complexity of the disease, the most common and effective treatments consist of a multi-therapy approach, including psychological, social, and pharmacological support with antidepressant drugs. In general, antidepressants are effective in correcting chemical imbalances of neurotransmitters in the brain, but recent evidence has underlined the pivotal role of gut microbiota (GM) also in the regulation of their pharmacokinetics/pharmacodynamics, through indirect or direct mechanisms. The study of these complex interactions between GM and drugs is currently under the spotlight, and it has been recently named "pharmacomicrobiomics". Hence, the purpose of this review is to summarize the contribution of GM and its metabolites in depression, as well as their role in the metabolism and activity of antidepressant drugs, in order to pave the way for the personalized administration of antidepressant therapies.

In Vitro and In Silico Studies of Neolignans from Magnolia grandiflora L. Seeds against Human Cannabinoids and Opioid Receptors

Magnolia grandiflora L. (Magnoliaceae) is a plant of considerable medicinal significance; its flowers and seeds have been used in various traditional remedies. Radioligand binding assays of n-hexane seeds extract showed displacement of radioligand for cannabinoid (CB1 and CB2) and opioid δ (delta), κ (kappa), and µ (mu) receptors. Bioactivity-guided fractionation afforded 4-O-methylhonokiol (1), magnolol (2), and honokiol (3), which showed higher binding to cannabinoid rather than opioid receptors in radioligand binding assays. Compounds 1-3, together with the dihydro analog of 2 (4), displayed selective affinity towards CB2R (K_i values of 0.29, 1.4, 1.94, and 0.99 μM, respectively), compared to CB1R (K_i 3.85, 17.82, 14.55, and 19.08 μM, respectively). An equal mixture of 2 and 3 (1:1 ratio) showed additive displacement activity towards the tested receptors compared to either 2 or 3 alone, which in turn provides an explanation for the strong displacement activity of the n-hexane extract. Due to the unavailability of an NMR or X-ray crystal structure of bound neolignans with the CB1 and CB2 receptors, a docking study was performed to predict ligand-protein interactions at a molecular level and to delineate structure-activity relationships (SAR) of the neolignan analogs with the CB1 and CB2 receptors. The putative binding modes of neolignans 1-3 and previously reported related analogs (4, 4a, 5, 5a, 6, 6a, and 6b) into the active site of the CB1 and CB2 receptors were assessed for the first time via molecular docking and binding free-energy (∆G) calculations. The docking and ∆G results revealed the importance of a hydroxyl moiety in the molecules that forms strong H-bonding with Ser383 and Ser285 within CB1R and CB2R, respectively. The impact of a shift from a hydroxyl to the methoxy group on experimental binding affinity to CB1R versus CB2R was explained through ∆G data and the orientation of the alkyl chain within the CB1R. This comprehensive SAR, influenced by the computational study and the observed in vitro displacement binding affinities, has indicated the potential of magnolia neolignans for developing new CB agonists for potential use as analgesics, anti-inflammatory agents, or anxiolytics.

Amelioration of lipopolysaccharides-induced impairment of fear memory acquisition by alpha-glycosyl isoquercitrin through suppression of neuroinflammation in rats

This study investigated the role of neuroinflammation in a lipopolysaccharides (LPS)-induced cognitive dysfunction model in rats using an antioxidant, α-glycosyl isoquercitrin (AGIQ). Six-week-old rats were dietary treated with 0.5% (w/w) AGIQ for 38 days, and LPS at 1 mg/kg body weight was administered intraperitoneally once daily on Days 8 and 10. On Day 11, LPS alone increased or tended to increase interleukin-1β and tumor necrosis factor-α in the hippocampus and cerebral cortex. Immunohistochemically, LPS alone increased the number of Iba1⁺ and CD68⁺ microglia, and GFAP⁺ astrocytes in the hilus of the hippocampal dentate gyrus (DG). AGIQ treatment decreased or tended to decrease brain proinflammatory cytokine levels and the number of CD68⁺ microglia in the DG hilus. In the contextual fear conditioning test during Day 34 and Day 38, LPS alone impaired fear memory acquisition, and AGIQ tended to recover this impairment. On Day 38, LPS alone decreased the number of DCX⁺ cells in the neurogenic niche, and AGIQ increased the numbers of PCNA⁺ cells in the subgranular zone and CALB2⁺ hilar interneurons. Additionally, LPS alone decreased or tended to decrease the number of synaptic plasticity-related FOS⁺ and COX2⁺ granule cells and AGIQ recovered them. The results suggest that LPS administration induced acute neuroinflammation and subsequent impairment of fear memory acquisition caused by suppressed synaptic plasticity of newborn granule cells following disruptive neurogenesis. In contrast, AGIQ exhibited anti-inflammatory effects and ameliorated LPS-induced adverse effects. These results suggest that neuroinflammation is a key factor in the development of LPS-induced impairment of fear memory acquisition.

Repurposing antimalarial artesunate for the prophylactic treatment of depression: Evidence from preclinical research

INTRODUCTION

Several studies have linked inflammation and oxidative stress with the pathogenesis of depression. Artesunate is a commonly used medication to treat malaria and has been shown to produce antioxidant, anti-inflammatory, and immunomodulatory effects. However, its prophylactic effects on depression and depression-related brain pathology are unknown.

METHODS

In Experiment 1, using a PC12 cell line, we investigated whether artesunate can prevent hydrogen peroxide (H₂ O₂ )-induced oxidative injury that mimics oxidative stress commonly observed in the depressed brain. Next, using lipopolysaccharide (LPS)-induced mouse model of depression, we investigated whether artesunate can prevent behavioral deficits observed in the open field test, novelty-suppressed feeding test, sucrose preference test, forced swimming test, and tail suspension procedure.

RESULTS

We found that artesunate significantly prevented a H₂ O₂ -induced reduction in PC12 cell activity, suggesting its antioxidant potential. We also found that mice pretreated with artesunate (5, 15 mg/kg) intraperitoneally (i.p.) prior to the LPS (.8 mg/kg, i.p.) treatment showed fewer and less severe depression- and anxiety-like behaviors than the LPS-treated control mice.

CONCLUSION

Our findings indicate that artesunate produces antioxidant effect, as well as antidepressant and anxiolytic effects. Importantly, our findings first demonstrate that artesunate can prevent LPS-induced depression- and anxiety-like symptoms, strongly suggesting its prophylactic potential in the treatment of depression and, perhaps, other psychiatric disorders associated with inflammation and oxidative stress.

The Neuropharmacological Effects of Magnolol and Honokiol: A Review of Signal Pathways and Molecular Mechanisms

Magnolol and honokiol are natural lignans with good physiological effects. As the main active substances derived from Magnolia officinalis, their pharmacological activities have attracted extensive attention. It is reported that both of them can cross the blood-brain barrier (BBB) and exert neuroprotective effects through a variety of mechanisms. This suggests that these two ingredients can be used as effective therapeutic compounds to treat a wide range of neurological diseases. This article provides a review of the mechanisms involved in the therapeutic effects of magnolol and honokiol in combating diseases, such as cerebral ischemia, neuroinflammation, Alzheimer's disease, and brain tumors, as well as psychiatric disorders, such as anxiety and depression. Although magnolol and honokiol have the pharmacological effects described above, their clinical potential remains untapped. More research is needed to improve the bioavailability of magnolol and honokiol and perform experiments to examine the therapeutic potential of magnolol and honokiol.

Honokiol Reduces Mitochondrial Dysfunction and Inhibits Apoptosis of Nerve Cells in Rats with Traumatic Brain Injury by Activating the Mitochondrial Unfolded Protein Response

This study was designed to determine the effects and underlying mechanism of honokiol (HNK) on traumatic brain injury (TBI). A rat TBI model was constructed using the modified Feeney free-fall percussion method and treatment with HNK via intraperitoneal injection. The brain tissues of the rats in each group were assessed using the terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay to detect the level of neuronal apoptosis. Western blots were used to detect the expression levels of apoptosis-related proteins (Bcl-2 and Bax), and ELISAs were used to measure the levels of pro-inflammatory cytokines (IL-18 and IL-1β) and the activity of caspase-1. In addition, the mitochondrial membrane potential, reactive oxygen species (ROS), and adenosine 5'-triphosphate (ATP) were also measured. Western blots and qRT-PCRs were used to determine the relative expression levels of the mitochondrial unfolded protein response (UPRmt)-related proteins and mRNAs. Based on the experimental results, treatment with HNK was associated with a decrease in the number of TUNEL-positive cells, downregulated Bax expression levels, elevated Bcl-2 expression levels, and inhibition of neuronal apoptosis in the brain tissue of TBI rats. HNK also suppressed neuroinflammation by decreasing IL-1β and IL-18 levels and caspase-1 activity. Additionally, HNK lowered the mitochondrial membrane potential and ROS levels, increased ATP levels, and improved mitochondrial dysfunction in neural cells. Furthermore, in the investigation of the mechanism of HNK on TBI, we observed that HNK could activate UPRmt by upregulating the mRNA and protein expression levels of HSPA9, CLPP, and HSP60 in the brain tissues of TBI rats. Collectively, HNK reduced mitochondrial dysfunction, inhibited the apoptosis of nerve cells, and attenuated inflammation in the brains of TBI rats. The protective effect of HNK may be achieved through the activation of UPRmt.

LQFM212, a piperazine derivative, exhibits potential antioxidant effect as well as ameliorates LPS-induced behavioral, inflammatory and oxidative changes

AIMS

Oxidative stress, impaired antioxidant defense and neuroinflammation are often associated with the onset and progression of neuropsychiatric diseases. Conversely, several piperazine compounds presents beneficial neuropharmacological effects as well as antioxidant activity, and some derivatives combine both activities. LQFM212 (2,6-di-tert-butyl-4-((4-(2-hydroxyethyl)piperazin-1-yl)methyl)phenol) was synthesized to produce effects on CNS and to have an additional antioxidant effect. Previous preclinical tests have been shown anxiolytic- and antidepressant-like effects of LQFM212 in mice. Herein, the main objective was to verify the possible antioxidant potential and the effects of LQFM212 against behavioral changes, inflammatory and oxidative markers induced by lipopolysaccharide (LPS).

MAIN METHODS

Initially, antioxidant potential of LQFM212 was evaluated by electrochemical assays. Afterwards, the effects of oral treatment with LQFM212 were evaluated in mice using LPS-induced models of systemic or local inflammation.

KEY FINDINGS

In LPS-induced neuroinflammation, LQFM212 treatment reverted changes caused by LPS, demonstrated by attenuated anxiogenic- and depressive-like behaviors, reduced pro-inflammatory cytokines (TNF-α and IL-1β) and increased anti-inflammatory cytokines (IL-4 and IL-10) on serum, and also improved oxidative stress-related changes (levels of nitrite, malondialdehyde, glutathione and carbonylated protein, and superoxide dismutase, catalase, myeloperoxidase and cholinesterase activities) on brain cortex and hippocampus. However, LQFM212 treatment did not attenuate the inflammatory changes in LPS-induced pleurisy model.

SIGNIFICANCE

LQFM212 presents antioxidant activity and ameliorates behavioral, inflammatory and oxidative changes after LPS-induced neuroinflammation model. These effects do not seem to be secondary to a peripheral anti-inflammatory action of LQFM212, since this compound failed to attenuate the inflammatory changes in LPS-induced pleurisy model.

Lipidomics reveals the potential mechanism of honokiol against adenine-induced chronic kidney disease

Honokiol (HKL), a biphenolic compound, is derived from the bark of Magnolia officinalis, which is used in traditional Chinese medicine for gastrointestinal complaints. HKL has diverse pharmacological activities and has protective effects in various disease models. However, the role and mechanism of HKL in treating chronic kidney disease (CKD) remain unclear. This study was designed to investigate whether HKL can alleviate CKD and the potential mechanism by which it acts. Male Sprague-Dawley rats were fed 0.75% w/w adenine feed for 3 weeks to induce CKD. HKL was administered by gavage at a dose of 5 mg/kg/day for 4 weeks. Using a special kit, serum creatinine (Scr) and blood urea nitrogen (BUN) were measured. To assess renal pathology, periodic acid-Schiff and Masson’s trichrome staining were conducted. Renal lipid profiles were analyzed by ultra-high-performance liquid chromatography/mass spectrometry (UHPLC/MS). The results showed that the administration of HKL reduced Scr and BUN and alleviated renal tubular atrophy and tubulointerstitial fibrosis in an adenine-induced CKD rat model. By using lipidomics, we identified 113 lipids (47 lipids in negative ion mode, 66 lipids in positive ion mode) that could be significantly reversed by HKL treatment in CKD rat kidneys. Most of these lipids belonged to the phosphatidylcholine (PC), ceramide (Cer), phosphatidylethanolamine (PE), and triacylglycerol (TAG) classes. Moreover, HKL improved fatty acid oxidation in the kidneys of CKD rats. In conclusion, this study found that HKL can protect against adenine-induced CKD, possibly through the regulation of lipid metabolism.

Neferine alleviates chronic stress-induced depression by regulating monoamine neurotransmitter secretion and gut microbiota structure

Neferine (Nef) might possess anti-depressive properties; however, its therapeutic effects are yet to be elucidated. Therefore, in this study, we aimed to explore the anti-depressant property of Nef using a mouse model of chronic stress-induced depression. Fifteen depression-prone mice were randomly selected and divided into three groups, namely, the model, Nef, and fluoxetine (Flu) groups. We observed that in tail suspension and forced swimming tests, the Nef and Flu treatments significantly decreased the immobility time of the depressed mice, and increased their sucrose preference indices. Moreover, both Nef and Flu treatments induced significant increases in the levels of anti-depressant neurotransmitters, including dopamine (DA), serotonin (5-HT), and norepinephrine (NE), and also reduced pathological damage to the hippocampus of the depressed mice. Incidentally, Illumina MiSeq sequencing analysis demonstrated that the relative abundance of Lactobacillus in the intestinal microbiota of depressed mice was restored after Nef/Flu treatment. Moreover, colonic Lactobacillus abundance was positively correlated with the levels of DA, 5-HT, and NE in the hippocampus of the mice. In conclusion, Nef improved monoamine neurotransmitter secretion and modulated the intestinal flora structure, particularly the abundance of Lactobacillus. Hence, it showed considerable anti-depressant potential, and might be a prospective anti-depressant therapeutic agent.

Honokiol improves depression-like behaviors in rats by HIF-1α- VEGF signaling pathway activation

Increasing evidence indicates that the pathogenesis of depression is closely linked to impairments in neuronal synaptic plasticity. Honokiol, a biologically active substance extracted from Magnolia Officinalis, has been proven to exert significant antidepressant effects. However, the specific mechanism of action remains unclear. In this study, PC12 cells and chronic unpredictable mild stress (CUMS) model rats were used to explore the antidepressant effects and potential mechanisms of honokiol in vitro and in rats. In vitro experiment, a cell viability detection kit was used to screen the concentration and time of honokiol administration. PC12 cells were administered with hypoxia-inducible factor-1α (HIF-1α) blocker, 2-methoxyestradiol (2-ME), and vascular endothelial growth factor receptor 2 (VEGFR-2) blocker, SU5416, to detect the expression of HIF-1α, VEGF, synaptic protein 1 (SYN 1), and postsynaptic density protein 95 (PSD 95) by western blotting. In effect, we investigated whether the synaptic plasticity action of honokiol was dependent on the HIF-1α-VEGF pathway. In vivo, behavioral tests were used to evaluate the reproducibility of the CUMS depression model and depression-like behaviors. Molecular biology techniques were used to examine mRNA and protein expression of the HIF-1α-VEGF signaling pathway and synaptic plasticity-related regulators. Additionally, molecular docking techniques were used to study the interaction between honokiol and target proteins, and predict their binding patterns and affinities. Experimental results showed that honokiol significantly reversed CUMS-induced depression-like behaviors. Mechanically, honokiol exerted a significant antidepressant effect by enhancing synaptic plasticity. At the molecular level, honokiol can activate the HIF-1α-VEGF signaling pathway in vitro and in vivo, as well as promote the protein expression levels of SYN 1 and PSD 95. Taken together, the results do not only provide an experimental basis for honokiol in the clinical treatment of depression but also suggest that the HIF-1α-VEGF pathway may be a potential target for the treatment of depression.

Ginsenoside Rh2 administration produces crucial antidepressant-like effects in a CUMS-induced mice model of depression

INTRODUCTION

The most striking feature of depression is sadness and a loss of interest in activities, which represents a major cause of disability globally. Therefore, it is necessary to identify novel antidepressants for clinical practice. Ginsenoside Rh2 (Rh2) is one of the major bioactive ginsenosides that can be extracted from Panax ginseng and has been demonstrated to improve both memory and learning. The purpose of this study was to provide broad insight into the mechanisms underlying depression and gain greater insights into antidepressant therapy.

METHODS

In this study, we first established an effective and feasible depression animal model of chronic unpredictable mild stress (CUMS) and behavioral testing was evaluated by the forced swim test (FST), the tail suspension test (TST) and the sucrose preference test. Following pretreatment with Rh2 (10 and 20 mg/kg), the immobility time of mice was reduced without affecting locomotor activity in both the FST and TST. Western blotting and immunofluorescence were used to investigate the activation of the hippocampal BDNF signaling pathway and hippocampal neurogenesis.

RESULTS

Different concentrations of Rh2 significantly reduced depressive-like symptoms in CUMS-induced mice and downregulated the effects of the BDNF signaling cascade and neurogenesis in the hippocampus. Furthermore, the administration of K252a completely prevented the antidepressant-like activity of Rh2 in mice.

CONCLUSION

The results indicated that Rh2 possesses the antidepression action via the positive regulation of the BDNF-TrkB pathway.

Autophagy:a new mechanism for esketamine as a depression therapeutic

Depression is a serious physical and mental disease, with major depressive disorder (MDD) being a hard-to-treat, life-threatening form of the condition. Currently, esketamine (ESK) is used in the clinical treatment of MDD, but the drug mechanisms continue to be unclear. In this study, we explored the therapeutic efficacy of ESK against lipopolysaccharide (LPS)-induced neuroinflammatory, autophagic, and depressive symptoms and the possible mechanisms behind them. Our study demonstrated that LPS increased cytokine levels (TNF-α, IL-1β, IL-6), induced neuroinflammation, led to increased levels of autophagy markers, and enhanced autophagy activation, which ultimately caused depressive symptoms in mouse models. ESK inhibited autophagy via the mTOR-BDNF signaling pathway and significantly alleviated the adverse effects induced by LPS, mainly in the form of reduced levels of cytokines, apoptotic factors, and autophagic markers; elevated BDNF levels; and improved depression-like behavior. Furthermore, we were interested to know if ESK in combination with other autophagy inhibitors would have a better antidepressant effect, and we chose the autophagy inhibitor 3-MA for this attempt. Interestingly, the use of 3-MA did not attenuate or even enhance the therapeutic effect of ESK. The results suggest that, in the LPS-induced depression models, ESK conveyed an antidepressant effect via the inhibition of autophagy through the mTOR-BDNF pathway.

Antidepressant-Like Effect and Mechanism of Ginsenoside Rd on Rodent Models of Depression

Background

There is growing evidence to suggest that ginsenoside Rd (GRd) has a therapeutic effect on depression, but the specific mechanisms behind its activity require further study.

Objective

This study is designed to investigate the antidepressant-like effect and underlying mechanisms of GRd.

Methods

In this study, the behavioral despair mouse model of depression and chronic unpredictable mild stress (CUMS) rat model of depression were established to explore the effects of GRd on depression-like behavior and its underlying mechanisms. Behavioral tests were used to evaluate the replication of animal models and depression-like behaviors. The hypoxia-inducible factor-1α (HIF-1α) blocker 2-methoxyestradiol (2-ME) was injected to determine the role of HIF-1α in the antidepressant-like effect of GRd. In addition, molecular biology techniques were used to determine the mRNA and protein expression of HIF-1ɑ signaling pathway and synaptic plasticity-related regulators, that is synapsin 1 (SYN 1) and postsynaptic density protein 95 (PSD 95). In silico binding interaction studies of GRd with focused target proteins were performed using molecular docking to predict the affinity and optimal binding mode between ligands and receptors.

Results

Our data show that GRd significantly reversed depression-like behavior and promoted mRNA and protein expression of HIF-1ɑ signaling pathway and synaptic plasticity-related regulators. However, the antidepressant-like effect of GRd disappeared upon inhibition of HIF-1α expression following administration of 2-ME. Furthermore, molecular docking results showed that GRd possessed significant binding affinity for HIF-1α, VEGF, and VEGFR-2.

Conclusion

Our results show that GRd exhibits significant antidepressant-like effect and that HIF-1α signaling pathway is a promising target for the treatment of depression.

Comparative Pharmacokinetic Study of Three Major Bioactive Components in the Normal and Different Courses of Liver-Stagnation and Spleen-Deficiency Syndrome Depressive Rats after Intragastric Administration of Zhi-Zi-Hou-Po Decoction

To reveal the pharmacokinetic process of narirutin, naringin, and honokiol in normal and different courses of liver-stagnation and spleen-deficiency syndrome depressive rats after intragastric administration of Zhi-Zi-Hou-Po decoction (ZZHPD), a rapid ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) method was proposed in this study. Chronic unpredictable mild stress (CUMS) rat was employed as the depression model. Acetonitrile solution containing 0.1% acetic acid and methyl alcohol-water (50 : 50, v/v) was chosen as the protein precipitant and redissolve solution severally; a Shim-pack GISS C₁₈ column coupled with 0.1% aqueous acetic acid-acetonitrile in gradient elution was employed to separate the mixed constituents in plasma. The WinNonLin software (version 6.1) was chosen as the analytical tool for the pharmacokinetic parameters. The results indicated that compared with rats in the control group, the sucrose preference, scores in the open-field test, and the concentration of 5-HT in plasma of rats in CUMS and CUMS + ZZHPD treatment groups were lower, while the immobility time in the forced swimming test of rats in these two groups was longer, which implied that the depression model was successful. These behavioral and biochemical indexes of rats above in the CUMS + ZZHPD treatment group were improved after oral administration of ZZHPD, which indicated that the antidepressant effect of ZZHPD was definite. The UHPLC-MS/MS method was stabilized, sensitive, and exclusive, and the extraction recovery and matrix effect of three analytes were all above 89%. The T _max, AUC, and C_max of three ingredients in CUMS-induced depression rats were significantly larger than control rats, while these pharmacokinetic parameters in CUMS + ZZHPD treatment rats were decreased significantly compared with CUMS-induced depression rats, which may relate with the changes in physiological function of the gastrointestinal tract and liver in CUMS-induced liver-stagnation and spleen-deficiency syndrome depressive rats. This study provided important information for the clinical rational use of ZZHPD in antidepressant treatment.

Extracellular Vesicles: Emerging Roles in Developing Therapeutic Approach and Delivery Tool of Chinese Herbal Medicine for the Treatment of Depressive Disorder

Extracellular vesicles (EVs) are lipid bilayer-delimited particles released by cells, which play an essential role in intercellular communication by delivering cellular components including DNA, RNA, lipids, metabolites, cytoplasm, and cell surface proteins into recipient cells. EVs play a vital role in the pathogenesis of depression by transporting miRNA and effector molecules such as BDNF, IL34. Considering that some herbal therapies exhibit antidepressant effects, EVs might be a practical delivery approach for herbal medicine. Since EVs can cross the blood-brain barrier (BBB), one of the advantages of EV-mediated herbal drug delivery for treating depression with Chinese herbal medicine (CHM) is that EVs can transfer herbal medicine into the brain cells. This review focuses on discussing the roles of EVs in the pathophysiology of depression and outlines the emerging application of EVs in delivering CHM for the treatment of depression.

Natural products for the treatment of stress-induced depression: Pharmacology, mechanism and traditional use

ETHNOPHARMACOLOGICAL RELEVANCE

Depression, one of the most common psychiatric disorders, is the fourth leading cause of long-term disability worldwide. A series of causes triggered depression, including psychological stress and conflict, as well as biological derangement, among which stress has a pivotal role in the development of depression. Traditional herbal medicine has been used for the treatment of various disorders including depression for a long history with multi-targets, multi-levels and multi-ways, attracting great attention from scholars. Recently, natural products have been commercialized as antidepressants which have become increasingly popular in the world health drug markets. Major research contributions in ethnopharmacology have generated and updated vast amount of data associated with natural products in antidepressant-like activity.

AIMS OF THE REVIEW

This review aims to briefly discuss the pathological mechanism, animal models of stress-induced depression, traditional use of herbal medicines and especially recapitulate the natural products with antidepressant activity and their pharmacological functions and mechanism of action, which may contribute to a better understanding of potential therapeutic effects of natural products and the development of promising drugs with high efficacy and low toxicity for the treatment of stress-induced depression.

MATERIALS AND METHODS

The contents of this review were sourced from electronic databases including PubMed, Sci Finder, Web of Science, Science Direct, Elsevier, Google Scholar, Chinese Knowledge On frastructure (CNKI), Wan Fang, Chinese Scientific and Technological Periodical Database (VIP) and Chinese Biomedical Database (CBM). Additional information was collected from Yao Zhi website (https://db.yaozh.com/). Data were obtained from April 1992 to June 2021. Only English language was applied to the search. The search terms were 'stress-induced depression', 'pathological mechanism' in the title and 'stress', 'depression', 'animal model' and 'natural products' in the whole text.

RESULTS

Stress-induced depression is related to the monoaminergic system, hypothalamic-pituitary-adrenal (HPA) axis, neuronal plasticity and a series of inflammatory factors. Four main types of animal models of stress-induced depression were represented. Fifty-eight bioactive phytochemical compounds, fifty-six herb medicines and five formulas from traditional Chinese medicine were highlighted, which exert antidepressant effects by inhibiting monoamine oxidase (MAO) reaction, alleviating dysfunction of the HPA axis and nerve injury, and possessing anti-inflammatory activities.

CONCLUSIONS

Natural products provide a large number of compounds with antidepressant-like effects, and their therapeutic impacts has been highlighted for a long time. This review summarized the pathological mechanism and animal models of stress-induced depression, and the natural products with antidepressant activity in particular, which will shed light on the action mechanism and clinical potential of these compounds. Natural products also have been a vital and promising source for future antidepressant drug discovery.

Ginsenoside Rb1 prevents lipopolysaccharide-induced depressive-like behavior by inhibiting inflammation and neural dysfunction and F2 elicits a novel antidepressant-like effect: A metabolite-based network pharmacology study

ETHNOPHARMACOLOGICAL RELEVANCE

Inflammatory responses are associated wieh the pathophysiology of depression. Ginsenoside Rb1 (Rb1) exerts antidepressant effect, but the relationship between its activity and inflammation remains unclear.

AIM OF THE STUDY

In this study, the antidepressant-like effect and underlying mechanisms of Rb1 were been investigated.

MATERIALS AND METHODS

The neuroinflammatory mouse model of lipopolysaccharide (LPS)-induced acute depression-like behavior was employed to detect the action of Rb1. An integrative strategy combining the identification of prototype (Rb1) and its metabolites in vivo with network pharmacology analysis was used to explore therapeutic mechanisms of these ingredients. The putative targets and signalings were experimentally validated. The antidepressant-like effect of F2, the metabolite of Rb1, was firstly evaluated.

RESULTS

Rb1 significantly ameliorated LPS-induced depressive-like behavior. Rb1 and its metabolites (Rd, F2, compound K, Rh2, Rg3, PPD) were identified and then a disease-component-target network was established. Experimental validation showed that Rb1 inhibited peripheral and hippocampal inflammation via MAPK/NF-κB signaling. In inflammatory-mediated depression state, Rb1 improved impaired glucocorticoid receptor, suppressed indoleamine 2,3-dioxygenase activity, increased 5-HT level and 5-HT_1A receptor expression. Additionally, F2 was firstly discovered to exert antidepressant-like effect, and it existed higher activity than Rb1 against depression.

CONCLUSION

The study highlighted the potential of Rb1 and F2 as healthy supplement or agent for inflammation-induced depression.

Lipopolysaccharide induced altered signaling pathways in various neurological disorders

Neuroinflammation is defined as an inflammatory response within the brain or spinal cord, whereas the brain's innate immune system is triggered by various inflammatory challenges such as injury, infection, exposure to toxin (LPS) and ageing, which result in cognitive impairment and neurodegenerative diseases including Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and multiple sclerosis (MS). Lipopolysaccharide (LPS) is a main structural component of the outer membrane of gram-negative bacteria, widely used systematically to stimulate the immune system and to generate profound physiological and behavioural changes. It consists of three parts: lipid A, a core oligosaccharide and an O side chain. It is reported by several scientists that, besides the systemic alteration, LPS also induces neurodegeneration by promoting neuroinflammation upon binding with the stimulation of Toll-like receptor-4 (TLR4) receptors present on glial cells. The mammalian Toll-like receptor (TLR) family consists of 13 membranes and TLR was discovered as a crucial pattern recognition receptor (PPR) involved in the recognition of pathogen-associated molecular patterns (PAMPs). Future studies will show that damage/danger-associated molecular patterns (DAMPs) are recognised by the involvement of PPRs, generated by the host itself. The stimulation of TLR4 by lipopolysaccharide phosphorylates two signalling pathways, namely the MyD88-dependent pathway and the MyD88-independent pathway. This activation subsequently triggers the release of various pro-inflammatory cytokines that are necessary to activate innate immune responses, and then promotes neuroinflammation. In this review, we critically demonstrated the epidemiology of neuroinflammation, types of TLRs, the molecular mechanism of TLR4 and management of neuroinflammation.

The rich pharmacological activities of Magnolia officinalis and secondary effects based on significant intestinal contributions

ETHNOPHARMACOLOGICAL RELEVANCE

Magnolia officinalis Cortex (M. officinalis) is a traditional herbal drug widely used in Asian countries. Depending on its multiple biological activities, M. officinalis is used to regulate gastrointestinal (GI) motility, relieve cough and asthma, prevent cardiovascular and cerebrovascular diseases, and treat depression and anxiety.

AIM OF THE REVIEW

We aimed to review the abundant form of pharmacodynamics activity and potential mechanisms of action of M. officinalis and the characteristics of the internal processes of the main components. The potential mechanisms of local and distance actions of M. officinalis based on GI tract was provided, and it was used to reveal the interconnections between traditional use, phytochemistry, and pharmacology.

MATERIALS AND METHODS

Published literatures about M. officinalis and its main components were collected from several scientific databases, including PubMed, Elsevier, ScienceDirect, Google Scholar and Web of Science etc. RESULTS: M. officinalis was shown multiple effects including effects on digestive system, respiratory system, central system, which is consistent with traditional applications, as well as some other activities such as cardiovascular system, anticancer, anti-inflammatory and antioxidant effects and so on. The mechanisms of these activities are abundant. Its chief ingredients such as magnolol and honokiol can be metabolized into active metabolites in vivo, which can increase water solubility and bioavailability and exert pharmacological activity in the whole body. In the GI tract, M. officinalis and its main ingredient can regulate GI hormones and substance metabolism, protect the intestinal barrier and affect the gut microbiota (GM). These actions are effective to improve local discomfort and some distal symptoms such as depression, asthma, or metabolic disorders.

CONCLUSIONS

Although M. officinalis has rich pharmacological effects, the GI tract makes great contributions to it. The GI tract is not only an important place for absorption and metabolism but also a key site to help M. officinalis exert local and distal efficacy. Pharmacodynamical studies on the efficacies of distal tissues based on the contributions of the GI tract hold great potential for understanding the benefits of M. officinalis and providing new ideas for the treatment of important diseases.

Integrated Network Pharmacology Analysis and Experimental Validation to Investigate the Mechanism of Zhi-Zi-Hou-Po Decoction in Depression

Zhi-Zi-Hou-Po Decoction (ZZHPD) is a well-known traditional Chinese medicine (TCM) that has been widely used in depression. However, the antidepressant mechanism of ZZHPD has not yet been fully elucidated. The purpose of this study was to explore the pharmacological mechanisms of ZZHPD acting on depression by combining ultra flow liquid chromatography with quadrupole time-of-flight mass spectrometry (UFLC-Q-TOF/MS) and network pharmacology strategy. The chemical components of ZZHPD were identified using UFLC-Q-TOF/MS, while the potential drug targets and depression-related targets were collected from databases on the basis of the identified compounds of ZZHPD. Protein-protein interaction (PPI) network, gene ontology (GO), and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analyses were used to unravel potential antidepressant mechanisms. The predicted antidepressant targets from the pharmacology-based analysis were further verified in vivo. As a result, a total of 31 chemical compounds were identified by UFLC-Q-TOF/MS; 514 promising drug targets were mined by using the Swiss Target Prediction; and 527 depression-related target genes were pinpointed by the GeneCards and OMIM databases. STRING database and Cytoscape's topological analysis revealed 80 potential targets related to the antidepressant mechanism of ZZHPD. The KEGG pathway analysis revealed that the antidepressant targets of ZZHPD were mainly involved in dopaminergic synapse, serotonin synapse, cAMP, and mTOR signaling pathways. Furthermore, based on the animal model of depression induced by chronic corticosterone, the regulatory effects of ZZHPD on the expression of MAOA, MAOB, DRD2, CREBBP, AKT1, MAPK1, HTR1A, and GRIN2B mRNA levels as well as the cAMP signaling pathway and monoaminergic metabolism were experimentally verified in rats. Our study revealed that ZZHPD is expounded to target various genes and pathways to perform its antidepressant effect.

Plant Extracts in Obesity: A Role of Gut Microbiota

Obesity has become one of the most serious chronic diseases threatening human health. Its occurrence and development are closely associated with gut microbiota since the disorders of gut microbiota can promote endotoxin production and induce inflammatory response. Recently, numerous plant extracts have been proven to mitigate lipid dysmetabolism and obesity syndrome by regulating the abundance and composition of gut microbiota. In this review, we summarize the potential roles of different plant extracts including mulberry leaf extract, policosanol, cortex moutan, green tea, honokiol, and capsaicin in regulating obesity via gut microbiota. Based on the current findings, plant extracts may be promising agents for the prevention and treatment of obesity and its related metabolic diseases, and the mechanisms might be associated with gut microbiota.

Mechanism and therapeutic strategies of depression after myocardial infarction

Depression resulted as an important factor associated with the myocardial infarction (MI) prognosis. Patients with MI also have a higher risk for developing depression. Although the issue of depression after MI has become a matter of clinical concern, the molecular mechanism underlying depression after MI remains unclear, whereby several strategies suggested have not got ideal effects, such as selective serotonin reuptake inhibitors. In this review, we summarized and discussed the occurrence mechanism of depression after MI, such as 5-hydroxytryptamine (5-HT) dysfunction, altered hypothalamus-pituitary-adrenal (HPA) axis function, gut microbiota imbalance, exosomal signal transduction, and inflammation. In addition, we offered a succinct overview of treatment, as well as some promising molecules especially from natural products for the treatment of depression after MI.

Neuroinflammation decreased hippocampal microtubule dynamics in the acute behavioral deficits induced by intracerebroventricular injection of lipopolysaccharide in male adult rats

Neuroinflammation plays a vital role in the pathology of depression. Microtubule dynamics produces an immediate response to stress, but the effect of microtubule dynamics in the rats with acute behavioral deficits following a central immune challenge remains elusive. Adult male Sprague-Dawley rats were subjected to the intracerebroventricular (icv) injection of lipopolysaccharide (. Behavioral tests, including bodyweight, sucrose preference test (SPT), forced swimming test (FST) and open field test (OFT), were performed to evaluate anxiety-like and depressive-like phenotypes at 24 h after injection, and some neuroinflammation biomarkers and microtubule dynamics in the hippocampus were detected. Lipopolysaccharide decreased the bodyweight, sucrose preference in SPT (depressive-like behavior), spontaneous activity in OFT (anxiety-like behavior) and increased the immobility time in FST (depressive-like behavior). Besides, lipopolysaccharide increased the mRNA levels of hippocampal CD11b and ionized calcium binding adaptor molecule (Iba1), which suggest microglial activation, and also upregulated hippocampal NLR Family Pyrin Domain Containing 3 inflammasome/interleukin-18/nuclear factor kappa-B mRNA. Lipopolysaccharide injection(icv) reduced the ratio of Tyr-/Acet-tubulin, an important marker of microtubule dynamics, in the acute behavioral deficit rats. Specifically, a decrease in Tyr-tubulin and an increase in the expression of Acet-tubulin were observed, indicating weakened microtubule dynamics. Pearson correlation analysis further showed that there was a significant negative correlation between hippocampal microtubule dynamics and neuroinflammatory activity. This study confirmed that hippocampal microtubule dynamics was decreased in the rats with acute behavioral deficits following a central immune challenge.

Phytochemicals in cancer and their effect on the PI3K/AKT-mediated cellular signalling

Protein kinases belong to the largest family of enzymes controlling every aspect of cellular activity including gene expression, cell division, differentiation and metabolism. They are part of major intracellular signalling pathways. Hence, it is not surprising that they are involved in the development of major diseases such as cardiovascular disorders, diabetes, dementia and, most importantly, cancer when they undergo mutations, modifications and unbalanced expression. This review will explore the possibility to draw a connection between the application of natural phytochemicals and the treatment of cancer. We have chosen to focus on the PI3K/AKT cellular signalling pathway which has been shown to be a major target by natural compounds in cell cultures and animal models.