Ninjinyoeito Improves Behavioral Abnormalities and Hippocampal Neurogenesis in the Corticosterone Model of Depression

Renshen Yangrong decoction for secondary malaise and fatigue: network pharmacology and Mendelian randomization study

Background

Renshen Yangrong decoction (RSYRD) has been shown therapeutic effects on secondary malaise and fatigue (SMF). However, to date, its bioactive ingredients and potential targets remain unclear.

Purpose

The purpose of this study is to assess the potential ingredients and targets of RSYRD on SMF through a comprehensive strategy integrating network pharmacology, Mendelian randomization as well as molecular docking verification.

Methods

Search for potential active ingredients and corresponding protein targets of RSYRD on TCMSP and BATMAN-TCM for network pharmacology analysis. Mendelian randomization (MR) was performed to find therapeutic targets for SMF. The eQTLGen Consortium (sample sizes: 31,684) provided data on cis-expression quantitative trait loci (cis-eQTL, exposure). The summary data on SMF (outcome) from genome-wide association studies (GWAS) were gathered from the MRC-IEU Consortium (sample sizes: 463,010). We built a target interaction network between the probable active ingredient targets of RSYRD and the therapeutic targets of SMF. We next used drug prediction and molecular docking to confirm the therapeutic value of the therapeutic targets.

Results

In RSYRD, network pharmacology investigations revealed 193 possible active compounds and 234 associated protein targets. The genetically predicted amounts of 176 proteins were related to SMF risk in the MR analysis. Thirty-seven overlapping targets for RSYRD in treating SMF, among which six (NOS3, GAA, IMPA1, P4HTM, RB1, and SLC16A1) were prioritized with the most convincing evidence. Finally, the 14 active ingredients of RSYRD were identified as potential drug molecules. The strong affinity between active components and putative protein targets was established by molecular docking.

Conclusion

This study revealed several active components and possible RSYRD protein targets for the therapy of SMF and provided novel insights into the feasibility of using Mendelian randomization for causal inference between Chinese medical formula and disease.

Glucocorticoid Receptor Down-Regulation Affects Neural Stem Cell Proliferation and Hippocampal Neurogenesis

Dysregulation of the hypothalamic-pituitary-adrenal axis and abnormalities in the glucocorticoid receptor (GR) have been linked to major depressive disorder. Given the critical role of GR in stress response regulation, we investigated the impact of GR changes on neural stem cells (NSCs) proliferation and hippocampal neurogenesis. Stress response was induced using dexamethasone (DEX), a GR agonist, which led to reduced proliferation of neural stem cells and neural progenitor cells, as well as decreased expression of GR. Additionally, a reduction of serum concentration within the culture media resulted in suppressed cell proliferation, accompanied by decreased GR expression. The association between GR expression and cell proliferation was further confirmed through GR siRNA knockdown and overexpression experiments. Furthermore, in vivo studies utilizing young male C57BL/6 mice demonstrated that corticosterone (CORT) (35 μg/ml) administered through drinking water for four weeks induced depression-like behavior, as indicated by increased immobility times in forced swimming and tail suspension tests. CORT exposure led to reduced GR and nestin expression levels, along with diminished numbers of BrdU-positive cells in the hippocampi, indicating impaired hippocampal neurogenesis. Taken together, our findings provide the first evidence that stress-induced downregulation of GR negatively affects neurogenesis by inhibiting NSCs proliferation.

The protective effects of Ninjin'yoeito against liver steatosis/fibrosis in a non-alcoholic steatohepatitis model mouse

Non-alcoholic steatohepatitis (NASH) is a progressive fibrotic form of non-alcoholic fatty liver disease. Liver fibrosis leads to liver cancer and cirrhosis, and drug therapy for NASH remains lacking. Ninjin'yoeito (NYT) has shown antifibrotic effects in a model of liver fibrosis without steatosis but has not been studied for NASH. Therefore, we evaluated the efficacy of NYT in mice fed a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) as a NASH model. Compared with the normal diet group, mice fed CDAHFD showed decreased body weight and increased white adipose tissue, liver weight, and triglyceride content in the liver. Furthermore, a substantial increase in the hepatic concentration of hydroxyproline, expression of α-smooth muscle actin (α-SMA), and transforming growth factor-β was observed in CDAHFD-fed mice. Masson's trichrome and Picro-Sirius red staining revealed a remarkable increase in collagen fiber compared with the normal diet group. Compared with mice that received CDAHFD alone, those supplemented with NYT exhibited reduced hepatic triglyceride and hydroxyproline levels and α-SMA expression. Additionally, compared with the group fed CDAHFD alone, the stained liver tissues of NYT-treated mice exhibited a reduction in Masson's trichrome- and Picro-Sirius red-positive areas. Locomotor activity was significantly reduced in the CDAHFD-fed group compared with the normal diet group. In the NYT-treated group, the CDAHFD-induced decrease in locomotor activity was significantly suppressed. The findings indicate that NYT inhibited fatty and fibrotic changes in the livers of NASH mice and alleviated the decrease in locomotor activity. Therefore, NYT may serve as a novel therapeutic approach for NASH.

Ninjinyoeito Prevents Onset of Depression-Like Behavior and Reduces Hippocampal iNOS Expression in Senescence-Accelerated Mouse Prone 8 Mice

Late-life depression is a globally prevalent disorder. Ninjinyoeito (NYT), a traditional Japanese herbal medicine, attenuates depressive symptoms in older patients. However, the mechanisms underlying the antidepressive effect of NYT are unknown. In this study, we investigated the mechanism of the action of NYT using senescence-accelerated mouse prone 8 (SAMP8) mice, which exhibit accelerated aging. SAMP8 mice were treated with NYT starting at 12 weeks of age. Twelve-week-old SAMP8 mice did not show prolonged immobility time in the tail suspension test compared with age-matched SAMR1 mice (normal aging control). At 34 weeks of age, vehicle-treated SAMP8 mice displayed prolonged immobility time compared with SAMR1 mice. NYT-treated SAMP8 mice showed a shorter immobility time than that of vehicle-treated SAMP8 mice. Notably, NYT decreased hippocampal inducible nitric oxide synthase (iNOS) expression in SAMP8 mice. There was no difference in iNOS expression between SAMR1 and vehicle-treated SAMP8 mice. Subchronic (5 days) administration of an iNOS inhibitor, 1400 W, shortened the immobility time in SAMP8 mice. These results suggest that NYT prevents an increase in immobility time of SAMP8 mice by decreasing iNOS levels in the hippocampus. Therefore, the antidepressive effect of NYT in older patients might be mediated, at least in part, by the downregulation of iNOS in the brain. Our data suggest that NYT is useful to prevent the onset of depression with aging.

Effects of Ninjin'yoeito on Human CYP3A and Mouse CYP3A Activity

Ninjin'yoeito (NYT) is widely used clinically for the management of patients with frailty and other multiple symptoms. NYT is often administered with other drugs; however, little information is available on its drug interactions. Previous studies using human liver microsomes have reported that constituents of NYT either inhibit (schisandra fruit, cinnamon bark, glycyrrhiza, and poria sclerotium) or induce (schisandra fruit and glycyrrhiza) CYP3A4 expression. Herein, we conducted in vitro and in vivo studies targeting human CYP3A and mouse CYP3A to elucidate the effects of NYT coadministration with other drugs on hepatic drug metabolism. In an inhibition study using human liver microsomes, NYT showed concentration-dependent reversible inhibition and time-dependent inhibition. Furthermore, in an induction study using frozen human hepatocytes, the addition of 0.01-0.1 mg/mL NYT resulted in a concentration-dependent increase in CYP3A gene expression. Contrarily, no significant changes in CYP3A substrate blood concentrations were observed between untreated mice and mice that received either a single dose of NYT or repeated doses for 15 days. These results demonstrate that NYT has inhibitory and inductive effects on hepatic CYP3A in vitro, but orally administered NYT does not affect drug metabolism mediated by hepatic CYP3A in vivo in the mouse model. Although there is a little information about drug interactions of NYT, this study provides new evidence for that.

Ninjin'yoeito Improves Genitourinary Symptoms in Patients With Frailty

Introduction In geriatric medicine, there is currently significant attention on frailty, a condition commonly associated with aging and characterized by muscle weakness and other age-related changes. Within the fields of urology and gynecology, conditions such as overactive bladder (OAB) and genitourinary syndrome of menopause (GSM) have been identified as crucial concerns due to their negative impact on the quality of life of elderly individuals. In this study, we investigated the potential of Ninjin'yoeito (NYT), a traditional Chinese herbal medicine, as a viable treatment option for frailty. Additionally, we hypothesized that NYT may also contribute to the improvement of symptoms associated with OAB and GSM, and potentially help in reducing the dosage of OAB medications. Methods In this retrospective cohort study conducted from November 2016 to November 2022, we created a website describing the relationship between frailty and genitourinary symptoms in frail patients aged ≥ 65 years with GSM who underwent pelvic floor muscle training. The patients were divided into two propensity score-matched groups: NYT group (received NYT for one year) and no-NYT group (did not receive NYT), based on their wishes. The fatigue, resistance, ambulation, illnesses, and loss of weight (FRAIL) scale was used to assess frailty status. Urinary symptoms were evaluated using the International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF) and Overactive Bladder Symptom Score (OABSS). Genital symptoms were investigated using the vaginal health index score and vulvodynia swab test. The value of each score was obtained before (T0) and 12 months after (T12) treatment, and the difference (Δ_T0/T12) was calculated. Results During the study period, 985 outpatients visited our clinic, of whom 725 were considered frail/pre-frail; 402 women with frailty/pre-frailty (mean age 77.5 ± 6.49 years) were included, with a median follow-up of 14.5 months. The NYT and no-NYT groups had 220 and 182 patients, respectively. After propensity score matching, each group had 159 patients. Δ_T0/T12FRAIL scale score was significantly higher in the NYT group (0.13 ± 0.37) than in the no-NYT (0.01 ± 0.10) group (p=0.001.) However, urinary symptoms improved in the NYT group more than in the no-NYT in terms of the following parameters: Δ_T0/T12OABSS (NYT: 0.89 ± 1.65; no-NYTl: 0.36 ± 1.14, p=0.001) and Δ_T0/T12ICIQ-SF score (NYT: 1.51 ± 1.75; no-NYT: 0.42 ± 1.18, p<0.001). Genital symptoms were better in the NYT group in terms of _ΔT0/T12VHIS (NYT: 0.58 ±1.08; no-NYT: 0.21 ±0.65, p<0.001). The vulvodynia swab test showed improvements in left para-hymen evoked pain in both groups. In the NYT group, 5% of the patients underwent antimuscarinic drug dose reduction for overactive bladder treatment. NYT use was not associated with significant side effects, and only 0.6% of patients reported drug allergies. Conclusion NYT improved activity levels in frail/pre-frail patients. Moreover, NYT use improved various genitourinary symptoms experienced by patients with frailty/pre-frailty. Treatment with NYT may reduce the dose of overactive bladder medications. The anticholinergic load-reducing effect of NYT may help solve the problem of polypharmacy.

Stimulation of functional recovery via neurorepair mechanisms by the traditional Japanese Kampo medicine, Ninjin'yoeito, and physical exercise in a rat ischemic stroke model

ETHNOPHARMACOLOGICAL RELEVANCE

Ninjin'yoeito (NYT), a traditional Japanese Kampo medicine consisting of 12 herbs, has been reported to improve cognitive dysfunction, depression, and neurological recovery in patients with neurovascular diseases such as Alzheimer's disease and stroke. Several studies have reported that the NYT components exert neurotrophic, neurogenic, and neuroprotective effects. In addition, exercise enhances neuroprotection and functional recovery after stroke. Rehabilitative exercises and pharmacological agents induce neurophysiological plasticity, leading to functional recovery in stroke patients. These reports indicate that NYT treatment and exercise may promote functional recovery following stroke through their beneficial effects. However, no study has determined the effects of NYT and the possible mechanisms of neurorepair and functional recovery after stroke.

AIM OF THE STUDY

This study aimed to investigate the combined effects of NYT and exercise on neuroprotection and functional recovery and the underlying mechanisms in a rat ischemic stroke model.

MATERIALS AND METHODS

Stroke was induced with 60-min middle cerebral artery occlusion (MCAO) followed by reperfusion in adult male Sprague-Dawley rats. After stroke, the rats were assigned to four groups: ischemia reperfusion (IR), NYT, exercise (Ex), and NYT + Ex. NYT-treated rats were fed a diet containing 1% NYT one day after stroke. Exercise was performed using a motorized treadmill for 5 days a week (8-15 m/min, 20 min/day), starting 3 days after stroke. The NYT treatment and exercise were continued for 4 weeks after the stroke. Infarct volume, neurological deficits, sensorimotor functions, expression of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), tropomyosin receptor kinase A (TrkA) and B (TrkB), caspase-3 activity, and the p-Akt/Akt ratio were examined by immunohistochemistry and western blotting.

RESULTS

Compared to the IR group, all treated groups indicated reduced infarct volumes. The NYT + Ex group showed significantly improved waking time and beam walking score compared with the IR group. The expression of NGF/TrkA/p-TrkA and BDNF/TrkB was significantly increased in the NYT + Ex group compared with those in the IR group, whereas the number of caspase-3 positive cells around the lesion was significantly lower in the NYT + Ex group than in the IR group. In addition, the ratio of p-Akt/Akt was significantly higher in the NYT + Ex group than in the IR group.

CONCLUSIONS

This study suggests that NYT in combination with exercise provides neuroprotective effects and improves sensorimotor function by stimulating NGF/TrkA and BDNF/TrkB, and by activating the Akt pathway in ischemic stroke of rats. NYT may be an effective adjunctive agent in post-stroke rehabilitation.

What can traditional Chinese medicine do for adult neurogenesis?

Adult neurogenesis plays a crucial role in cognitive function and mood regulation, while aberrant adult neurogenesis contributes to various neurological and psychiatric diseases. With a better understanding of the significance of adult neurogenesis, the demand for improving adult neurogenesis is increasing. More and more research has shown that traditional Chinese medicine (TCM), including TCM prescriptions (TCMPs), Chinese herbal medicine, and bioactive components, has unique advantages in treating neurological and psychiatric diseases by regulating adult neurogenesis at various stages, including proliferation, differentiation, and maturation. In this review, we summarize the progress of TCM in improving adult neurogenesis and the key possible mechanisms by which TCM may benefit it. Finally, we suggest the possible strategies of TCM to improve adult neurogenesis in the treatment of neuropsychiatric disorders.

Ninjin'yoeito suppressed the onset of arthritis, pain, and muscle atrophy in rheumatoid arthritis model mice

Rheumatoid arthritis is one of the most common diseases in orthopedic surgery. The main symptoms are joint pain and systemic symptoms. In recent years, rheumatoid arthritis is known to cause sarcopenia. Ninjin'yoeito (NYT), a traditional Japanese medicine, has been prescribed for patients with post-illness or post-operative weakness, fatigue, loss of appetite, rash, cold limbs, and anemia. In addition to its traditional use, NYT has been prescribed for treating frailty in gastrointestinal, respiratory, and urinary functions. Further, NYT is known to be effective in suppressing muscle atrophy in the prior literature. The present study aimed to investigate whether NYT suppresses various symptoms of the Collagen-induced arthritis (CIA) model. Long-term administration of NYT inhibited the increases in arthritis scores, decreases pain threshold, and muscle atrophy in the CIA model. In addition, NYT inhibited the elevation of the plasma IL-6 level. These results suggest that NYT may have therapeutic effects on symptoms, muscle atrophy and increase in plasma IL-6 level caused by rheumatoid arthritis.

Impact of Ninjin’yoeito on frailty and short life in klotho-hypomorphic (kl/kl) mice

With the recent aging of society, the prevention of frailty has become an important issue because people desire both a long and healthy lifespan. Klotho-hypomorphic (kl/kl) mice are known to show phenotypes of premature aging. Ninjin’yoeito (NYT) is a traditional Japanese Kampo medicine used to treat patients with vulnerable constitution, fatigue or physical exhaustion caused by aging and illness. Recent studies have reported the potential efficacy of NYT against frailty. We therefore evaluated the effect of NYT on the gait function, activity, the histopathological status of organs and survival using kl/kl mice as a model of aging-related frailty. Two sets of 28-day-old male kl/kl mice were assigned to the vehicle (non-treated; NT), 3% or 5% NYT dietary groups. One set of groups (NT, n = 18; 3% NYT, n = 11; 5% NYT, n = 11) was subjected to the analysis of free walking, rotarod, and spontaneous activity tests at approximately 58 days old. Thereafter, we measured triceps surae muscles weight and myofiber cross-sectional area (CSA), and quantified its telomere content. In addition, we evaluated bone strength and performed histopathological examinations of organs. Survival was measured in the second set of groups (NT, 3% NYT and 5% NYT group, n = 8 each). In the walking test, several indicators such as gait velocity were improved in the NYT 3% group. Similar results were obtained for the latency to fall in the rotarod test and spontaneous motor activity. Triceps muscle mass, CSA and its telomere content were significantly improved in the NYT 3% group. Bone density, pulmonary alveolus destruction and testicular atrophy were also significantly improved in the NYT 3% group. Survival rate and body weight were both significantly improved in the NYT3% group compared with those in the NT group. Continuous administration of NYT from the early stage of aging improved not only gait performance, but also the survival in the aging-related frailty model. This effect may be associated with the improvements in aging-related organ changes such as muscle atrophy. Intervention with NYT against the progression of frailty may contribute to a longer, healthier life span among the elderly individuals.

Ninjinyoeito improves social behavior disorder in neuropeptide Y deficient zebrafish

Sociability is an essential component of the linkage structure in human and other vertebrate communication. Low sociability is defined as a poor social approach, including social withdrawal and apathy, and is implicated in a variety of psychiatric disorders. Ninjinyoeito (NYT), a traditional Japanese herbal medicine, has been used in the medical field. This study aimed to determine the effect of NYT on low sociality in NPY-KO zebrafish. NPY-KO zebrafish were fed a 3% NYT-supplemented diet for 4 days and subjected to behavioral tests. In the mirror test, NPY-KO zebrafish fed a control diet showed avoidance behavior toward their mirror counterparts. In contrast, the treatment of NPY-KO zebrafish with NYT significantly increased their interaction with their counterparts in the mirror. In addition, a 3-chambers test was conducted to confirm the effect of NYT on the low sociality of NPY-KO zebrafish. NPY-KO zebrafish fed the control diet showed less interaction with fish chambers, while NYT treatment increased the interaction. Phosphorylation of ERK, a marker of neuronal activity, was significantly reduced in the whole brain of NYT-fed NPY-KO zebrafish, compared to the control diet. NYT treatment significantly suppressed hypothalamic-pituitary-adrenal-related genes (gr, pomc, and crh) and sympathetic-adrenal-medullary-related genes (th1, th2, and cck) in NPY-KO zebrafish. NYT administration significantly reduced mRNA levels of gad1b compared to the control diet, suggesting the involvement of GABAergic neurons in NYT-induced improvement of low sociability. Furthermore, the expression of CREB was suppressed when NPY-KO zebrafish were fed NYT. Next, we attempted to identify the effective herb responsible for the NYT-induced improvement of low sociability. NPY-KO zebrafish were fed an experimental diet containing the target herb for 4 days, and its effect on sociability was evaluated using the 3-chambers test. Results showed that Cinnamon Bark and Polygala Root treatments significantly increased time spent in the fish tank area compared to the control diet, while the other 10 herbs did not. We confirmed that these two herbs suppressed the activity of HPA-, SAM-, and GABAergic neurons, as well as NYT-treated zebrafish, accompanied by downregulation of CREB signaling. This study suggests the potential use of NYT as a drug for sociability disorders.

A quasi-randomized controlled trial of Ninjin'yoeito for the treatment of postpartum anemia and the prevention of postpartum depression

AIM

To study the effect of Ninjin'yoeito (NYT) on postpartum anemia and on the development of postpartum depression (PPD).

METHODS

In this prospective, single-center, open-label, quasi-randomized controlled trial, patients with anemia 1-2 days postdelivery were randomized to receive either NYT or an oral iron preparation for 4 weeks. The primary endpoint was the hemoglobin (Hb) level. Secondary endpoints were fatigue (assessed by the numerical rating scale [NRS]) and prevalence of postpartum depressive symptoms, as defined by an Edinburgh postnatal depression scale (EPDS) score ≥9. Hb levels and fatigue were measured before, and 4 weeks after, treatment and the EPDS was measured 4 weeks posttreatment.

RESULTS

Of 1066 participants (NYT group: 532, iron group: 534) 1061 (NYT group: 529, iron group: 532) underwent full analysis. The Hb level increased significantly in both groups (p < 0.001), and there were no significant differences between the groups in terms of the change in Hb levels (NYT: 2.4 ± 0.8 g/dL vs. iron: 2.5 ± 0.7 g/dL, p = 0.098). Fatigue decreased significantly in the NYT group (p < 0.001) but did not change in the iron group, and the difference was significant (p < 0.001). There was a significant difference between the two groups in terms of the prevalence of postpartum depressive symptoms (NYT: 5.7% vs. iron: 9.4%, odds ratio [OR] = 0.58, 95% confidence interval [CI] = 0.36-0.93).

CONCLUSION

The results suggest that NYT improves postpartum anemia and fatigue, and may be able to prevent the development of PPD.

Safety and efficacy of Ninjin'yoeito along with iron supplementation therapy for preoperative anemia, fatigue, and anxiety in patients with gynecological disease: an open-label, single-center, randomized phase-II trial

Background

Preoperative anemia affects perioperative outcomes and often causes fatigue and psychological disorders. Therefore, anemia should be treated before a patient undergoes surgery. Ninjin’yoeito (NYT), a Japanese Kampo medicine composed of ginseng and Japanese angelica root with the other 10 herbs, is administered for anemia, fatigue and anxiety; however, there are a few reports that have prospectively examined the effects of NYT before surgery for gynecological diseases. Hence, we tended to investigate its efficacy and safety.

Methods

In this open-label randomized trial, women with gynecological diseases accompanied by preoperative anemia (defined as < 11.0 g/dL Hemoglobin [Hb]) were randomly assigned (1:1) into the iron supplementation and NYT groups. Patients of the iron supplementation group and the NYT group received 100 mg/day iron supplementation with and without NYT (7.5 g/day) for at least 10 days before surgery. The primary endpoint was improvement in Hb levels before and after treatment, and Cancer Fatigue Scale (CFS) and Visual Analogue Scale for Anxiety (VAS-A) scores between groups. Statistical analyses were performed with Wilcoxon signed rank test, Wilcoxon rank sum test, and Fisher’s exact test as appropriate.

Results

Forty patients were enrolled of whom 30 patients were finally analyzed after allocating 15 to each group. There was no difference in the characteristics between both groups. Hb significantly increased in both groups (iron supplementation group, 9.9 ± 0.8 g/dL vs. 11.9 ± 1.6 g/dL; NYT group, 9.8 ± 1.0 g/dL vs. 12.0 ± 1.0 g/dL); the difference in the elevations in Hb between both groups was statistically insignificant (P = 0.72). Contrarily, CFS (17.9 ± 10.2 vs. 8.1 ± 5.2) and VAS-A (56 mm (50–70) vs. 23 mm (6–48)) scores were significantly decreased only in the NYT group and these changes were greater in the NYT group (∆CFS, P = 0.015; ∆VAS-A, P = 0.014). Liver dysfunction occurred in one patient of the NYT group.

Conclusions

For treating preoperative anemia in women with gynecological conditions, NYT administration along with iron supplementation safely and efficiently improved the preoperative fatigue and anxiety in addition to the recovery from anemia.

Trial registration: jRCT1051190012 (28/April/2019, retrospectively registered).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12905-022-01824-9.

Ninjinyoeito ameliorated cigarette smoke extract-induced apoptosis and inflammation through JNK signaling inhibition in human lung fibroblasts

BACKGROUND

Cigarette smoke is a major risk factor for various lung diseases, such as chronic obstructive pulmonary disease (COPD). Ninjinyoeito (NYT), a traditional Chinese medicine, has been prescribed for patients with post-illness or post-operative weakness, fatigue, loss of appetite, rash, cold limbs, and anemia. In addition to its traditional use, NYT has been prescribed for treating frailty in gastrointestinal, respiratory, and urinary functions. Further, NYT treatment can ameliorate cigarette smoke-induced lung injury, which is a destructive index in mice; however, the detailed underlying mechanism remains unknown. The purpose of this study was to investigate whether NYT ameliorates cigarette smoke-induced cell injury and inflammation in human lung fibroblasts and determine its mechanism of action.

METHODS

We prepared a cigarette smoke extract (CSE) from commercially available cigarettes to induce cell injury and inflammation in the human lung fibroblast cell line HFL1. The cells were pretreated with NYT for 24 h prior to CSE exposure. Cytotoxicity and cell viability were measured by lactate dehydrogenase (LDH) cytotoxicity assay and cell counting kit (CCK)-8. IL-8 level in the cell culture medium was measured by performing Enzyme-Linked Immuno Sorbent Assay (ELISA). To clarify the mechanisms of NYT, we used CellROX Green Reagent for reactive oxygen species (ROS) production and western blotting analysis for cell signaling.

RESULTS

Exposure of HFL1 cells to CSE for 24 h induced apoptosis and interleukin (IL)-8 release. Pretreatment with NYT inhibited apoptosis and IL-8 release. Furthermore, CSE exposure for 24 h increased the production of ROS and phosphorylation levels of p38 and JNK. Pretreatment with NYT only inhibited CSE-induced JNK phosphorylation, and not ROS production and p38 phosphorylation. These results suggest that NYT acts as a JNK-specific inhibitor.

CONCLUSION

NYT treatment ameliorated CSE-induced apoptosis and inflammation by inhibiting the JNK signaling pathway. Finally, these results suggest that NYT may be a promising therapeutic agent for patients with COPD.

Antidepressant effect of catalpol on corticosterone-induced depressive-like behavior involves the inhibition of HPA axis hyperactivity, central inflammation and oxidative damage probably via dual regulation of NF-κB and Nrf2

This study aimed to investigate the antidepressant effect and mechanism of catalpol on corticosterone (CORT)-induced depressive-like behavior in mice for the first time. As a result, CORT injection induced depressive-like behaviors of mice in behavioral tests, aggravated the serum CORT, adrenocorticotropic hormone, and corticotropin-releasing hormone levels, and conspicuously elevated the phosphorylations of nuclear factor kappa-B (NF-κB) in the hippocampus and frontal cortex, and down-regulated the expression levels of nuclear factor erythroid-2-related factor 2 (Nrf2). Furthermore, CORT exposure dramatically augmented the levels of inflammatory factors (interleukin-1β, tumor necrosis factor-α, nitric oxide synthase, and nitric oxide) and lipid peroxidation product malondialdehyde, and attenuated the levels of antioxidants including reduced glutathione, glutathione S-transferase, total superoxide dismutase, and heme oxygenase-1 in the mouse hippocampus and frontal cortex. On the contrary, catalpol administration markedly suppressed the abnormalities of the above indicators. From the overall results, this study displayed that catalpol exerted a beneficial effect on CORT-induced depressive-like behavior in mice possibly via the inhibition of hypothalamus-pituitary-adrenal (HPA) axis hyperactivity, central inflammation and oxidative damage at least partially through dual regulation of NF-κB and Nrf2.

Protective effects of VMY-2-95 on corticosterone-induced injuries in mice and cellular models

Nicotinic α4β2 receptor antagonists have drawn increasing attention in the development of new antidepressants. In this study, we aimed to investigate the protective effect of VMY-2-95, the new selective antagonist of α4β2 nicotinic acetylcholine receptor (nAChR) on corticosterone (CORT) injured mice and cellular models. Fluoxetine was applied as a positive control, and the effects of VMY-2-95 were investigated with three different doses or concentrations (1, 3, 10 mg/kg in mice, and 0.003, 0.03, 0.1 μmol/L in cells). As a result, VMY-2-95 showed significant antidepressant-like effects in the CORT injured mice by improving neuromorphic function, promoting hippocampal nerve proliferation, and regulating the contents of monoamine transmitters. Meanwhile, VMY-2-95 exhibited protective effects on cell viability, cell oxidant, cell apoptosis, and mitochondrial energy metabolism on corticosterone-impaired SH-SY5Y cells. Also, the PKA-CREB-BDNF signaling pathway was up-regulated by VMY-2-95 both in vitro and in vivo, and pathway blockers were also combined with VMY-2-95 to verify the effects furtherly. Therefore, we preliminarily proved that VMY-2-95 had protective effects in depressed mice and SH-SY5Y cells against injuries induced by corticosterone. This work indicated that the application of VMY-2-95 is a potential pharmacological solution for depression. This study also supported the development of α4β2 nAChR antagonists towards neuropsychiatric dysfunctions.

Ninjinyoeito improves anxiety behavior in neuropeptide Y deficient zebrafish

Anxiety induced by excess mental or physical stress is deeply involved in the onset of human psychiatric diseases such as depression, bipolar disorder, and panic disorder. Recently, Kampo medicines have received focus as antidepressant drugs for clinical use because of their synergistic and additive effects. Thus, we evaluated the anxiolytic activity of Ninjinyoeito (NYT) using neuropeptide Y-knockout (NPY-KO) zebrafish that exhibit severe anxiety responses to acute stress. Adult NPY-KO zebrafish were fed either a 3% NYT-supplemented or normal diet (i.e., the control diet) for four days and were then examined via behavioral tests. After short-term cold stress (10 °C, 2 s) was applied, control-fed NPY-KO zebrafish exhibited anxiety behaviors such as freezing, erratic movement, and increased swimming time along the tank wall. On the other hand, NYT-fed NPY-KO zebrafish significantly suppressed these anxiety behaviors, accompanied by a downregulation of tyrosine hydroxylase levels and phosphorylation of extracellular signal-regulated kinases in the brain. To understand the responsible component(s) in NYT, twelve kinds of herbal medicines that composed NYT were tested in behavioral trials with the zebrafish. Among them, nine significantly reduced freezing behavior in NPY-KO zebrafish. In particular, Schisandra fruit induced the most potent effect on abnormal zebrafish behavior, even in the lower amount (0.3% equivalent to NYT), followed by Atractylodes rhizome and Cinnamon bark. Subsequently, four lignans uniquely found in Schisandra fruit (i.e., gomisin A, gomisin N, schizandrin, and schizandrin B) were investigated for their anxiolytic activity in NPY-KO zebrafish. As a result, schizandrin was identified as a responsible compound in the anxiolytic effect of NYT. These results suggest that NYT has a positive effect on mental stress-induced anxiety and may be a promising therapeutic for psychiatric diseases.

Chronic running and a corticosterone treatment attenuate astrocyte-like neural stem cell proliferation in the area postrema of the adult mouse brain

The discovery of neural stem cells (NSCs) in the adult mammalian brain has provided insights into an extra level of brain plasticity. The proliferation and differentiation of NSCs is modulated by various physiological, pathological, and pharmacological stimuli. NSCs were recently detected in the medulla oblongata of adult rodents and humans; however, their functional significance currently remains unknown. In the present study, we examined the effects of chronic wheel-running and a corticosterone (CORT) treatment on the proliferation of astrocyte-like NSCs in the area postrema (AP) and dentate gyrus (DG). Chronic running significantly decreased the number of bromodeoxyuridine (BrdU)-labeled astrocyte-like NSCs in the AP of adult mice, but markedly increased that of BrdU+ NSCs/neural progenitor cells in the DG. The chronic CORT treatment markedly reduced the number of BrdU+ astrocyte-like NSCs in the AP, but not in the DG. These results demonstrate that the proliferation of astrocyte-like NSCs in the medulla oblongata is decreased by chronic running and a CORT treatment.

Ninjin'yoeito Alleviates Neuropathic Pain Induced by Chronic Constriction Injury in Rats

Kampo medicines are frequently used empirically to treat pain in clinical practice. Ninjin'yoeito (NYT), which is associated with few adverse effects, is often used to treat the elderly, but has not yet been examined in detail. We herein investigated the effects of NYT, at 500 and 1,000 mg/kg p.o. (NYT500/NYT1000 group) in single and repeated administrations for 14 days, on pain in rats with peripheral neuropathy induced by loose ligation of the sciatic nerve (chronic constriction injury: CCI). Untreated CCI rats given distilled water were used as a control group. To assess induced pain, the pain threshold was measured using the von Frey test. To evaluate spontaneous pain, the ground-contact area of the paw with neuropathic pain was measured using the Dynamic Weight Bearing test. Serum samples were collected after the test to elucidate the mechanism of action of NYT, and brain-derived neurotrophic factor (BDNF) and corticosterone protein levels, which have been reported to change due to chronic pain, were analyzed. After single administration of NYT, the pain threshold rose in the NYT500 and NYT1000 groups. The pain threshold tended to rise on day 14 of repeated administration in the NYT500 group (p = 0.08) and it significantly rose at NYT1000 group (p < 0.05) compared to Control group. In addition, the foot contact area increased (p = 0.09). Therefore, CCI-induced pain was significantly remitted and spontaneous pain was remitted after repeated administration of NYT. Serum BDNF levels were higher in untreated CCI rats than in normal rats (p = 0.05), but decreased after the repeated administration of NYT (NYT1000, p = 0.15), while serum corticosterone levels were lower (p = 0.12) than those in normal rats and increased after the repeated administration of NYT (NYT1000, p = 0.07). The blood BDNF level has been suggested to influence pain intensity. The findings demonstrated NYT effectively treats neuropathic pain, suggesting that a NYT-induced decrease in blood BDNF contributed to the mechanism of pain relief. In addition, the variation of corticosterone was observed, suggesting that normalization of responsiveness to stress by NYT contributed to the pain relief.

Corticosterone induces neurotoxicity in PC12 cells via disrupting autophagy flux mediated by AMPK/mTOR signaling

Aims

Our previous study indicated that chronic stress caused autophagy impairment and subsequent neuron apoptosis in hippocampus. However, the mechanism underlying the stress‐induced damage to neurons is unclear. In present work, we investigated whether stress‐level glucocorticoids (GCs) GCs promoted PC12 cell damage via AMPK/mTOR signaling‐mediated autophagy.

Methods

Chronic stress‐induced PC12 cell injury model was built by treatment with high level corticosterone (CORT). Cell injury was evaluated by flow cytometry assay and transmission electron microscopy observation.

Results

Autophagy flux was measured based on the changes in LC3‐II and P62 protein expressions, and the color alteration of mCherry‐GFP‐LC3‐II transfection. Our results showed that CORT not only increased cell injury and apoptosis, but also dysregulated AMPK/mTOR signaling‐mediated autophagy flux, as indicated by the upregulated expression of LC3‐II and P62 proteins, and the lowered ration of autolysosomes to autophagosomes. Mechanistically, our results demonstrated that autophagy activation by AMPK activator metformin or mTOR inhibitor rapamycin obviously promotes cell survival and autophagy flux, improved mitochondrial ultrastructure, and reduced expression of Cyt‐C and caspase‐3 in CORT‐induced PC12 cells.

Conclusion

These results indicate that high CORT triggers PC12 cell damage through disrupting AMPK/mTOR‐mediated autophagy flux. Targeting this signaling may be a promising approach to protect against high CORT and chronic stress‐induced neuronal impairment.