JSH-23 prevents depressive-like behaviors in mice subjected to chronic mild stress: Effects on inflammation and antioxidant defense in the hippocampus

Astrocyte-specific inhibition of sigma-1 receptor leads to depressive-like behaviors in mice via activation of NF-κB-induced neuroinflammation

Major depressive disorder (MDD) is a global health burden characterized by persistent low mood, deprivation of pleasure, recurrent thoughts of death, and physical and cognitive deficits. The current understanding of the pathophysiology of MDD is lacking, resulting in few rapid and effective antidepressant therapies. Recent studies have pointed to the sigma-1 (σ-1) receptor as a potential rapid antidepressant target; σ-1 agonists have shown promise in a variety of preclinical depression models. Hypidone hydrochloride (YL-0919), an independently developed antidepressant by our institute with faster onset of action and low rate of side effects, has recently emerged as a highly selective σ-1 receptor agonist; however, its underlying astrocyte-specific mechanism is unknown. In this study, we investigated the effect of YL-0919 treatment on gene expression in the prefrontal cortex of depressive-like mice by single-cell RNA sequencing. Furthermore, we knocked down σ-1 receptors on astrocytes in the medial prefrontal cortex of mice to explore the effects of YL-0919 on depressive-like behavior and neuroinflammation in mice. Our results demonstrated that astrocyte-specific knockdown of σ-1 receptor resulted in depressive-like behavior in mice, which was reversed by YL-0919 administration. In addition, astrocytic σ-1 receptor deficiency led to activation of the NF-κB inflammatory pathway, and crosstalk between reactive astrocytes and activated microglia amplified neuroinflammation, exacerbating stress-induced neuronal apoptosis. Furthermore, the depressive-like behavior induced by astrocyte-specific knockdown of the σ-1 receptor was improved by a selective NF-κB inhibitor, JSH-23, in mice. Our study not only reaffirms the σ-1 receptor as a key target of the faster antidepressant effect of YL-0919, but also contributes to the development of astrocytic σ-1 receptor-based novel drugs.

Diosmin ameliorates LPS-induced depression-like behaviors in mice: Inhibition of inflammation and oxidative stress in the prefrontal cortex

Diosmin is a flavone glycoside with a confirmed therapeutic effectiveness on the chronic venous disorders. In this paper, the classical mouse depression model induced by LPS was established to explore the effect of Diosmin on depression. Firstly, we found that Diosmin could inhibit the inflammation and neuronal damage in the prefrontal cortex (PFC) of mice, and thus alleviating the LPS-induced depressive-like behaviors. Specifically, Diosmin treatment significantly suppressed the secretion of pro-inflammatory cytokines (TNF-α, IL-6 and IL-1β), reduced the activation of microglia, and inhibited the expression of NLRP3 inflammasome and its downstream effector caspase-1 in both PFC of mice and BV2 microglial cells exposed to LPS. Then, we demonstrated that pretreatment with Diosmin dramatically suppressed the LPS-induced oxidative stress in the PFC of mice, manifested in the decrease of reactive oxygen species and malondialdehyde while increase of catalase activity. Consistently, Diosmin also alleviated the oxidative stress in BV2 cells exposed to LPS. Finally, we confirmed that Diosmin effectively suppressed the activation of NF-κB signaling pathway in the PFC of LPS-treated mice. Further in vitro experiments also verified that Diosmin could prevent the p65 transposition to nucleus in LPS-treated BV2 cells, suggesting that the antidepressant effects of Diosmin are partially mediated by blocking of NF-κB signaling. Taken together, this study proposes the potential antidepressant effect of Diosmin, which provides useful support to the development of new therapies for depression.

Therapeutic modulation of JAK-STAT, mTOR, and PPAR-γ signaling in neurological dysfunctions

The cytokine-activated Janus kinase (JAK)-signal transducer and activator of transcription (STAT) cascade is a pleiotropic pathway that involves receptor subunit multimerization. The mammalian target of rapamycin (mTOR) is a ubiquitously expressed serine-threonine kinase that perceives and integrates a variety of intracellular and environmental stimuli to regulate essential activities such as cell development and metabolism. Peroxisome proliferator-activated receptor-gamma (PPARγ) is a prototypical metabolic nuclear receptor involved in neural differentiation and axon polarity. The JAK-STAT, mTOR, and PPARγ signaling pathways serve as a highly conserved signaling hub that coordinates neuronal activity and brain development. Additionally, overactivation of JAK/STAT, mTOR, and inhibition of PPARγ signaling have been linked to various neurocomplications, including neuroinflammation, apoptosis, and oxidative stress. Emerging research suggests that even minor disruptions in these cellular and molecular processes can have significant consequences manifested as neurological and neuropsychiatric diseases. Of interest, target modulators have been proven to alleviate neuronal complications associated with acute and chronic neurological deficits. This research-based review explores the therapeutic role of JAK-STAT, mTOR, and PPARγ signaling modulators in preventing neuronal dysfunctions in preclinical and clinical investigations.

Human macrophages and monocyte-derived dendritic cells stimulate the proliferation of endothelial cells through midkine production

The cytokine midkine (MK) is a growth factor that is involved in different physiological processes including tissue repair, inflammation, the development of different types of cancer and the proliferation of endothelial cells. The production of MK by primary human macrophages and monocyte-derived dendritic cells (MDDCs) was never described. We investigated whether MK is produced by primary human monocytes, macrophages and MDDCs and the capacity of macrophages and MDDCs to modulate the proliferation of endothelial cells through MK production. The TLR stimulation of human monocytes, macrophages and MDDCs induced an average of ≈200-fold increase in MK mRNA and the production of an average of 78.2, 62, 179 pg/ml MK by monocytes, macrophages and MDDCs respectively (p < 0.05). MK production was supported by its detection in CD11c+ cells, CLEC4C+ cells and CD68+ cells in biopsies of human tonsils showing reactive lymphoid follicular hyperplasia. JSH-23, which selectively inhibits NF-κB activity, decreased the TLR-induced production of MK in PMBCs, macrophages and MDDCs compared to the control (p < 0.05). The inhibition of MK production by macrophages and MDDCs using anti-MK siRNA decreased the capacity of their supernatants to stimulate the proliferation of endothelial cells (p = 0.01 and 0.04 respectively). This is the first study demonstrating that the cytokine MK is produced by primary human macrophages and MDDCs upon TLR triggering, and that these cells can stimulate endothelial cell proliferation through MK production. Our results also suggest that NF-κB plays a potential role in the production of MK in macrophages and MDDCs upon TLR stimulation. The production of MK by macrophages and MDDCs and the fact that these cells can enhance the proliferation of endothelial cells by producing MK are novel immunological phenomena that have potentially important therapeutic implications.

Possible Involvement of the IL-6/JAK2/STAT3 Pathway in the Hypothalamus in Depressive-Like Behavior of Rats Exposed to Chronic Mild Stress

INTRODUCTION

The interleukin-6/janus kinase 2/signal transducer and activator of transcription 3 (IL-6/JAK2/STAT3) pathway plays an important role in immune function, but little research has focused on this pathway in depression. We sought to examine the relationship between the IL-6/JAK2/STAT3 pathway and depressive-like behavior.

METHODS

Using a chronic mild stress (CMS) paradigm, a total of 36 adult male Sprague-Dawley rats were divided into four matched groups: (1) control + vehicle, (2) CMS + vehicle, (3) control + paroxetine, and (4) CMS + paroxetine. We investigated the effects of CMS on depressive-like behavior by using the forced swimming test (FST). Subsequently, the mRNA levels of members of the IL-6/JAK2/STAT3 pathway were assessed by qRT-PCR.

RESULTS

We found that rats exposed to CMS displayed a significant increase in immobility time and a decrease in climbing time in the FST. Moreover, mRNA levels of IL-6, JAK2, and STAT3 in the hypothalamus were increased following CMS. We also found that mRNA levels of IL-6, JAK2, and STAT3 were normalized by paroxetine administration, which coincided with normalization of the depressive-like behavior.

CONCLUSIONS

The IL-6/JAK2/STAT3 pathway may be activated in depression, and targeting this pathway may provide a novel effective therapeutic approach for the treatment of depression.

Copper-Binding Peptides Attenuate Microglia Inflammation through Suppression of NF-kB Pathway

SCOPE

Activation of microglia, the resident immune cells of the central nervous system, has been related to the etiology and progression of neurodegenerative diseases; thus, finding novel approaches to suppress the neuroinflammatory process is of utmost relevance.

METHODS AND RESULTS

The anti-inflammatory activity of whey Cu-, Fe-, and Zn-binding peptides and their possible underlying mechanism of action were evaluated in microglia. Whey metal-binding peptides decreased nitric oxide production and tumor necrosis factor α (TNF-α) at mRNA and protein levels by stimulated BV-2 microglia in comparison to the control with no peptide treatment. The hydrophobicity, specific sequences, and possible synergistic effects seem to play a role. Cu-binding peptides (Cu-bp) presented anti-inflammatory activity both in BV-2 and primary microglia cultures. These peptides exert their action by suppressing nuclear factor kappa B (NF-kB) pathway since nuclear translocation of NF-kB p65 is decreased by roughly 30% upon Cu-bp treatment. Specific sequences identified in Cu-bp showed high affinity to bind NF-kB p65 by molecular docking (up to -8.8 kcal mol-1 ), corroborating the immunofluorescence studies.

CONCLUSION

Cu-bp represent food-derived peptides that may be useful for neuroprotective purposes. Chelation of copper excess in the CNS and the bioavailability of such peptides, as well as their behavior in in vivo models, deserve further research for future applications.

The Novel Antioxidant Compound JSH-23 Prevents Osteolysis by Scavenging ROS During Both Osteoclastogenesis and Osteoblastogenesis

Inflammatory osteolysis is a pathological skeletal disease associated with not only the production of inflammatory cytokines but also local oxidative status. Excessive reactive oxygen species (ROS) promote bone resorption by osteoclasts and induce the apoptosis of osteoblasts. In consideration of the lack of effective preventive or treatments options against osteolysis, the exploitation of novel pharmacological compounds/agents is critically required. In our study, we found that a novel antioxidant compound, JSH-23, plays a role in restoring bone homeostasis by scavenging intracellular ROS during both osteoclastogenesis and osteoblastogenesis. Mechanically, JSH-23 suppressed RANKL-induced osteoclastogenesis, bone resorption and the expression of specific genes (including NFATc1, c-Fos, TRAP, CTSK and DC-STAMP) via inhibition of the NF-κB signaling pathway. Meanwhile, JSH-23 suppressed RANKL-induced ROS generation via the TRAF6/Rac1/NOX1 pathway and the enhanced expression of Nrf2/HO-1. In addition, JSH-23 attenuated H₂O₂-induced apoptosis and mineralization reduction in osteoblasts by reducing ROS production and enhancing Nrf2/HO-1 expression. Our in vivo results further revealed that JSH-23 exerts its protective effects on bone mass through its antioxidant activity. In conclusion, our results show that the application of JSH-23 might be a novel and plausible strategy for the treatment of osteolysis-related disease.

Sustained Inhibition of NF-κB Activity Mitigates Retinal Vasculopathy in Diabetes

This study investigated the effects of long-term NF-κB inhibition in mitigating retinal vasculopathy in a type 1 diabetic mouse model (Akita, Ins2^Akita). Akita and wild-type (C57BL/6J) male mice, 24 to 26 weeks old, were treated with or without a selective inhibitor of NF-κB, 4-methyl-N1-(3-phenyl-propyl) benzene-1,2-diamine (JSH-23), for 4 weeks. Treatment was given when the mice were at least 24 weeks old. Metabolic parameters, key inflammatory mediators, blood-retinal barrier junction molecules, retinal structure, and function were measured. JSH-23 significantly lowered basal glucose levels and intraocular pressure in Akita. It also mitigated vascular remodeling and microaneurysms significantly. Optical coherence tomography of untreated Akita showed thinning of retinal layers; however, treatment with JSH-23 could prevent it. Electroretinogram demonstrated that A- and B-waves in Akita were significantly smaller than in wild type mice, indicating that JSH-23 intervention prevented loss of retinal function. Protein levels and gene expression of key inflammatory mediators, such as NOD-like receptor family pyrin domain-containing 3, intercellular adhesion molecule-1, inducible nitric oxide synthase, and cyclooxygenase-2, were decreased after JSH-23 treatment. At the same time, connexin-43 and occludin were maintained. Vision-guided behavior also improved significantly. The results show that reducing inflammation could protect the diabetic retina and its vasculature. Findings appear to have broader implications in treating not only ocular conditions but also other vasculopathies.

Anti-Inflammatory Effects of Asian Fawn Lily (Erythronium japonicum) Extract on Lipopolysaccharide-Induced Depressive-Like Behavior in Mice

Neuroinflammation is associated with an increased risk of depression. Lipopolysaccharide (LPS) treatment is known to induce pro-inflammatory cytokine secretion and a depressive-like phenotype in mice. Although Erythronium japonicum exhibits various health benefits, the role of E. japonicum extract (EJE) in inflammation-associated depression is unknown. This study aimed to explore the anti-inflammatory effect of EJE on LPS-induced depressive symptoms in mice using the open field test (OFT), passive avoidance test (PAT), tail suspension test (TST), and forced swim test (FST). LPS-treated mice had significantly increased immobility time in the TST and FST, decreased step-through latency time in the PAT, and decreased locomotor activity in the OFT. However, administration of 100 and 300 mg/kg of EJE significantly improved these depressive-like behaviors. EJE also prevented the increase in mRNA levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, and monocyte chemoattractant protein-1 (MCP-1), and the decrease in IL-10 levels by inhibiting nuclear factor-κB (NF-κB) subunit p65 phosphorylation. Additionally, LPS-treated mice showed markedly decreased brain-derived neurotrophic factor (BDNF) levels and phosphorylation of phosphoinositide 3-kinase (PI3K) and Akt, while EJE treatment significantly increased these levels in the hippocampus. These results suggest that EJE ameliorated LPS-induced depressive-like behavior by reducing LPS-induced neuroinflammation and activating the BDNF-PI3K/Akt pathway.

The anti-inflammatory role of SSRI and SNRI in the treatment of depression: a review of human and rodent research studies

RATIONALE

Depression has the topmost prevalence of all psychiatric diseases. It is characterized by a high recurrence rate, disability, and numerous and mostly unclear pathogenic mechanisms. Besides the monoamine or the neurotrophic hypothesis of depression, the inflammatory mechanism has begun to be supported by more and more evidence. At the same time, the current knowledge about the standard treatment of choice, the selective serotonin reuptake inhibitors (SSRIs) and serotonin and noradrenaline reuptake inhibitors (SNRIs), is expanding rapidly, adding more features to the initial ones.

OBJECTIVES

This review summarizes the in vivo anti-inflammatory effects of SSRIs and SNRIs in the treatment of depression and outlines the particular mechanisms of these effects for each drug separately. In addition, we provide an overview of the inflammation-related theory of depression and the underlying mechanisms.

RESULTS

SSRIs and SNRIs decrease the neuroinflammation through multiple mechanisms including the reduction of blood or tissue cytokines or regulating complex inflammatory pathways: nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), inflammasomes, Toll-like receptor 4 (TLR4), peroxisome proliferator-activated receptor gamma (PPARγ). Also, SSRIs and SNRIs show these effects in association with an antidepressant action.

CONCLUSIONS

SSRIs and SNRIs have an anti-neuroinflammatory role which might contribute the antidepressant effect.

Hesperetin reverses P‑glycoprotein‑mediated cisplatin resistance in DDP‑resistant human lung cancer cells via modulation of the nuclear factor‑κB signaling pathway

Lung cancer is the leading cause of cancer-associated mortality worldwide. Cisplatin (DDP) is a first-line chemotherapeutic drug for the treatment of lung cancer; however, the majority of patients develop resistance to DDP. P-glycoprotein (P-gp), also referred to as multidrug resistance (MDR) protein 1, is associated with an MDR phenotype, which results in failure of cancer chemotherapy; thus, identifying effective MDR pump inhibitors may improve the outcomes of patients who develop resistance to treatment. Hesperetin is a derivative of hesperidin, which is extracted from tangerine peel and exhibits multiple antitumor properties. In the present study, human lung adenocarcinoma A549 and A549/DDP cells were treated with different concentrations of hesperetin and DDP, respectively. Furthermore, rhodamine 123 efflux assays, Cell Counting Kit-8 assays, immunofluorescence, reverse transcription-quantitative PCR and western blot analysis were used to elucidate the mechanisms underlying the effects of hesperetin On A549/DDP cells. Additionally, a xenograft model of lung cancer in nude mice was established to explore the effects of hesperetin on A549/DDP cell growth in vivo. The results demonstrated that hesperetin sensitized A549/DDP cells to DDP. In vivo, hesperetin pretreatment significantly inhibited tumor growth. Mechanistically, hesperetin markedly decreased the expression of P-gp and increased the intracellular accumulation of the P-gp substrate, rhodamine 123, in A549/DDP cells. In addition, pretreatment of A549/DDP cells with hesperetin significantly inhibited nuclear factor (NF)-κB (p65) activity and its nuclear translocation. Taken together, the results of the present study suggest that hesperetin reversed P-gp-mediated MDR by decreasing P-gp expression in A549/DDP cells, which was associated with inhibition of the NF-κB signaling pathway. These findings may provide the basis for the use of hesperetin clinically to reverse MDR.

Antidepressant-like effects of penta-acetyl geniposide in chronic unpredictable mild stress-induced depression rat model: Involvement of inhibiting neuroinflammation in prefrontal cortex and regulating hypothalamic-pituitaryadrenal axis

We previously reported that penta-acetyl geniposide ((Ac)₅GP, an acetylated derivative of geniposide) exhibited better pharmacological functions than geniposide, a major active component of Gardenia jasminoides Ellis. This study demonstrated the antidepressant-like effects of (Ac)₅GP and its involved mechanisms using a rat depression model caused by chronic unpredictable mild stress (CUMS). Behavioral tests including sucrose preference, open field and forced swimming were applied to evaluate depression symptoms. IL-1β, IL-6 and TNF-α mRNA and protein levels in prefrontal cortex (PFC) were respectively measured by quantitative PCR and ELISA. The protein levels of IκBα, p-IκBα, NF-κB p65, NLRP3, pro- and mature-IL-1β in PFC were determined by western blot. The activity of hypothalamic-pituitaryadrenal (HPA) axis was also measured. (Ac)₅GP treatment alleviated the CUMS-induced depressive-like behaviors in rats, as indicated by increased sucrose intake, increased total crossing and rearing numbers, improved central activity and reduced immobility time. (Ac)₅GP reversed the CUMS-induced elevations of IL-1β, IL-6 and TNF-α mRNA and protein levels in PFC. (Ac)₅GP reduced degradation and phosphorylation of IκBα and protein level of nuclear NF-κB p65 in PFC. (Ac)₅GP also decreased the mRNA and protein levels of NLRP3 and reduced the ratio of mature-IL-1β protein over total IL-1β protein (pro-IL-1β + mature-IL-1β) in PFC. Moreover, (Ac)₅GP reduced serum levels of adrenocorticotropic hormone/corticosterone and mRNA level of hypothalamic corticotrophin-releasing hormone. In conclusion, (Ac)₅GP treatment improved the depressive-like behaviors in CUMS rats perhaps by suppressing neuroinflammation in PFC and inhibiting activations of NF-κB and NLRP3 and also attenuating HPA axis hyperactivity.

Thyroxine Affects Lipopolysaccharide-Induced Macrophage Differentiation and Myocardial Cell Apoptosis via the NF-κB p65 Pathway Both In Vitro and In Vivo

Background

Numerous studies have demonstrated that the inflammatory response is involved in the progression of lipopolysaccharide- (LPS-) induced myocardial cell apoptosis. Accumulating evidence has shown that thyroxine participates in diseases by downregulating the inflammatory response. This study aimed at investigating whether thyroxine alleviates LPS-induced myocardial cell apoptosis.

Methods

Bone marrow-derived macrophages (Mø) were treated with LPS and thyroxine, and Mø differentiation and Mø-related cytokine expression were measured. The effect of Mø differentiation on mouse cardiomyocyte (MCM) apoptosis was also detected in vitro. In addition, C57BL/6 mice underwent thyroidectomy and were treated with LPS 35 days later; subsequently, Mø differentiation and myocardial cell apoptosis in hearts were analyzed. To determine whether the nuclear factor-kappa B (NF-κB) p65 pathway mediates the effect of thyroxine on Mø differentiation and myocardial cell apoptosis, the specific NF-κB p65 pathway inhibitor JSH-23 was administered to mice that underwent a thyroidectomy.

Results

Levothyroxine treatment significantly reduced the activation of the NF-κB p65 pathway, decreased M1 macrophage (Mø1) differentiation and Mø1-related cytokine mRNA levels in LPS-treated Mø, and increased M2 macrophage (Mø2) differentiation and Mø2-related cytokine mRNA expression. The protective effects of levothyroxine on MCM apoptosis mediated by LPS-treated Mø were alleviated by JSH-23. In mice, thyroidectomy aggravated LPS-induced cardiac injury and cardiac dysfunction, further promoted NF-κB p65 activation, and increased cardiac Mø1 expression and myocardial cell apoptosis but decreased cardiac Mø2 expression. JSH-23 treatment significantly ameliorated the thyroidectomy-induced increases in myocardial cell apoptosis and Mø differentiation.

Conclusions

Thyroxine alleviated the Mø1/Mø2 imbalance, reduced the inflammatory response, decreased myocardial cell apoptosis, and protected against cardiac injury and cardiac dysfunction in LPS-treated mice. Thyroxine may be a novel therapeutic strategy to prevent and treat LPS-induced cardiac injury.

The Chinese Herbal Formula PAPZ Ameliorates Behavioral Abnormalities in Depressive Mice

Major depressive disorder (MDD) is a chronic mental disorder characterized by mixed symptoms and complex pathogenesis. With long history of practical application, traditional Chinese medicine (TCM) offers many herbs for the treatment and rehabilitation of chronic disease. In this study, we developed a modified Chinese herbal formula using Panax ginseng, Angelica Sinensis, Polygala tenuifolia Willd, and Ziziphi spinosae Semen (PAPZ), based on an ancient TCM prescription. The antidepressant effects of PAPZ were investigated with a corticosterone (CORT) model of depression in mice. Our results showed that administration of PAPZ ameliorated depression-like phenotypes in the CORT model. An anatomic study showed that chronic PAPZ administration upregulated the protein expression of brain-derived neurotrophic factor (BDNF) in hippocampal tissue. The enzyme activity of superoxide dismutase was enhanced in hippocampal tissue, in line with a decreased malondialdehyde level. Taken together, these findings suggested that PAPZ has therapeutic effects in a mice depression model through increasing protein expression of BDNF and improving the anti-oxidation ability of the brain.