Electroacupuncture alleviates PTSD-like behaviors by modulating hippocampal synaptic plasticity via Wnt/ß-catenin signaling pathway.

Abnormalities in hippocampal synaptic plasticity contribute to the pathogenesis of post-traumatic stress disorder (PTSD). The Wnt/ß-catenin signaling pathway is critical for the regulation of synaptic plasticity. PTSD symptoms can be alleviated by correcting impaired neural plasticity in the hippocampus (Hipp). Electroacupuncture (EA) has a therapeutic effect by relieving PTSD-like behaviors. However, little is known about whether the Wnt/ß-catenin pathway is involved in EA-mediated improvements of PTSD symptoms. In this study, we found that enhanced single prolonged stress (ESPS)-induced PTSD led to abnormal neural plasticity, characterized by the decline of dendritic spines, the expression of postsynaptic density 95 (PSD95), and synaptophysin (Syn) in the stressed Hipp along with the reduction of Wnt3a and ß-catenin, and increased GSK-3ß. EA significantly alleviated PTSD-like behaviors, as assessed by the open field test, elevated platform maze test and conditioning fear test. This was paralleled by correcting abnormal neural plasticity by promoting the expression of PSD95 and Syn, as well as the number of dendritic spines in the Hipp. Importantly, EA exerted anti-PTSD effects by augmenting the expression levels of Wnt3a and ß-catenin, and decreasing that of GSK-3ß. The effects mediated by EA were abolished by XAV939, an inhibitor of the Wnt/ß-catenin pathway. This suggests that EA relieved ESPS-induced PTSD-like behaviors, which can largely be ascribed to impaired neural plasticity in the Hipp. These findings provide new insights into possible mechanisms linking neural plasticity in the Hipp as potential novel targets for PTSD treatment in EA therapy.

Praeruptorin C alleviates cognitive impairment in type 2 diabetic mice through restoring PI3K/AKT/GSK3ß pathway.

Diabetic encephalopathy is a common consequence of diabetes mellitus that causes cognitive dysfunction and neuropsychiatric disorders. Praeruptorin C (Pra-C) from the traditional Chinese medicinal herb Peucedanum praeruptorum Dunn. is a potential antioxidant and neuroprotective agent. This study was conducted to investigate the molecular mechanisms underlying the effect of Pra-C on diabetic cognitive impairment. A novel object recognition test and the Morris water maze test were performed to assess the behavioral performance of mice. Electrophysiological recordings were made to monitor synaptic plasticity in the hippocampus. A protein-protein interaction network of putative Pra-C targets was constructed, and molecular docking simulations were performed to predict the potential mechanisms of the action of Pra-C. Protein expression levels were detected by western blotting. Pra-C administration significantly lowered body weight and fasting blood glucose levels and alleviated learning and memory deficits in type 2 diabetic mice. Network pharmacology and molecular docking results suggested that Pra-C affects the PI3K/AKT/GSK3ß signaling pathway. Western blot analysis confirmed significant increases in phosphorylated PI3K, AKT, and GSK3ß levels in vivo and in vitro upon Pra-C administration. Pra-C alleviated cognitive impairment in type 2 diabetic mice by activating PI3K/AKT/GSK3ß pathway.

Tanshinone IIA improves contextual fear- and anxiety-like behaviors in mice via the CREB/BDNF/TrkB signaling pathway.

Posttraumatic stress disorder (PTSD) is one of the most common psychiatric diseases, which is characterized by the typical symptoms such as re-experience, avoidance, and hyperarousal. However, there are few drugs for PTSD treatment. In this study, conditioned fear and single-prolonged stress were employed to establish PTSD mouse model, and we investigated the effects of Tanshinone IIA (TanIIA), a natural product isolated from traditional Chinese herbal Salvia miltiorrhiza, as well as the underlying mechanisms in mice. The results showed that the double stress exposure induced obvious PTSD-like symptoms, and TanIIA administration significantly decreased freezing time in contextual fear test and relieved anxiety-like behavior in open field and elevated plus maze tests. Moreover, TanIIA increased the spine density and upregulated synaptic plasticity-related proteins as well as activated CREB/BDNF/TrkB signaling pathway in the hippocampus. Blockage of CREB remarkably abolished the effects of TanIIA in PTSD model mice and reversed the upregulations of p-CREB, BDNF, TrkB, and synaptic plasticity-related protein induced by TanIIA. The molecular docking simulation indicated that TanIIA could interact with the CREB-binding protein. These findings indicate that TanIIA ameliorates PTSD-like behaviors in mice by activating the CREB/BDNF/TrkB pathway, which provides a basis for PTSD treatment.

Scutellarin ameliorates the stress-induced anxiety-like behaviors in mice by regulating neurotransmitters.

Anxiety disorders are a common frequently psychiatric symptom in patients that lead to disruption of daily life. Scutellarin (Scu) is the main component of Erigeron breviscapus, which has been used as a neuroprotective agent against glutamate-induced excitotoxicity. However, the potential effect of Scu on the stress-related neuropsychological disorders has not been clarified. In this study, Anxiety-like behavior was induced by acute restraint stress in mice. Scu were injected intraperitoneally (twice daily, 3 days). Results showed that Scu exhibited good protective activity on mice by decreasing transmitter release levels. Restraint stress caused significant anxiety like behavior in mice. Treatment of Scu could significantly improve the moving time of open arms in Elevated Plus Maze and central time on open field test. Scu treatment suppressed action potential firing frequency, restored excessive presynaptic quantal release, and down-regulated glutamatergic receptor expression levels in the prefrontal cortex (PFC) of stressed mice. GABAA Rα1 and GABAA γ2 expression in the brain PFC tissues of mice were nearly abrogated by Scu treatment. In stress-induced anxiety mice, stress can increase the frequency of mini excitatory postsynaptic currents (mEPSC), which can be reversed by Scu treatment. Therefore, Scu has a potent anxiolytic activity and may be valuable for the treatment of stress-induced anxiety disorders.

Anxiolytic Effects of 8-O-Acetyl Shanzhiside Methylester on Acute and Chronic Anxiety via Inflammatory Response Inhibition and Excitatory/Inhibitory Transmission Imbalance.

Anxiety leads to a global decline in quality of life and increase in social burden. However, treatments are limited, because the molecular mechanisms underlying complex emotional disorders are poorly understood. We explored the anxiolytic effects of 8-O-acetyl shanzhiside methylester (8-OaS), an active component in Lamiophlomis rotata (L. rotata; Benth.) or Kudo, a traditional herb that has been shown to be effective in the clinical treatment of chronic pain syndromes in China. Two mouse anxiety models were used: forced swimming stress (FSS)-induced anxiety and complete Freund's adjuvant (CFA)-induced chronic inflammatory pain. All animal behaviors were analyzed on the elevated plus maze and in the open-field test. 8-OaS significantly ameliorated anxiety-like behaviors in both anxiety models and inhibited the translation enhancement of GluN2A, GluN2B, and PSD95. Moreover, a reduction in GABA receptors disrupted the excitatory/inhibitory (E/I) balance in the basolateral amygdala (BLA), indicated by increased excitatory and decreased inhibitory presynaptic release. 8-OaS also blocked microglia activation and reduced the phosphorylation of p38, c-Jun N-terminal kinase (JNK), NF-κB p65, and tumor necrosis factor alpha (TNF-α) in the BLA of anxiety mice. 8-OaS exhibits obvious anxiolytic effects by regulating the excitatory/inhibitory (E/I) synaptic transmission and attenuating inflammatory responses in the BLA.

Scopoletin ameliorates anxiety-like behaviors in complete Freund's adjuvant-induced mouse model.

Anxiety disorder is highly prevalent worldwide and represents a chronic and functionally disabling condition, with high levels of psychological stress characterized by cognitive and physiological symptoms. Scopoletin (SP), a main active compound in Angelica dahurica, is traditionally used for the treatment of headache, rhinitis, pain, and other conditions. Here, we evaluated the effects of SP in a mouse model of complete Freund's adjuvant (CFA)-induced chronic inflammation anxiety. SP (2.0, 10.0, 50.0 mg/kg) administration for 2 weeks dose-dependently ameliorated CFA-induced anxiety-like behaviors in the open field test and elevated plus maze test. Moreover, we found that SP treatment inhibited microglia activation and decreased both peripheral and central IL-1ß, IL-6, and TNF-α levels in a dose-dependent manner. Additionally, the imbalance in excitatory/inhibitory receptors and neurotransmitters in the basolateral nucleus after CFA injection was also modulated by SP administration. Our findings indicate that the inhibition of the nuclear factor-kappa B and mitogen-activated protein kinase signaling pathways involving anti-inflammatory activities and regulation of the excitatory/inhibitory balance can be attributed to the anxiolytic effects of SP. Moreover, our molecular docking analyses show that SP also has good affinity for gamma-aminobutyric acid (GABA) transaminase and GABAA receptors. Therefore, these results suggest that SP could be a candidate compound for anxiolytic therapy and for use as a structural base for developing new drugs.

Anxiolytic effects of Formononetin in an inflammatory pain mouse model.

Chronic pain is commonly accompanied with anxiety disorder, which complicates treatment. In this study, we investigated the analgesic and anxiolytic effects of Formononetin (FMNT), an active component of traditional Chinese medicine red clover (Trifolium pratense L.) that is capable of protecting neurons from N-methyl-D-aspartate (NMDA)-evoked excitotoxic injury, on mice suffering from complete Freund's adjuvant (CFA)-induced chronic inflammatory pain. The results show that FMNT administration significantly reduces anxiety-like behavior but does not affect the nociceptive threshold in CFA-injected mice. The treatment reverses the upregulation of NMDA, GluA1, and GABAA receptors, as well as PSD95 and CREB in the basolateral amygdala (BLA). The effects of FMNT on NMDA receptors and CREB binding protein (CBP) were further confirmed by the potential structure combination between these compounds, which was analyzed by in silico docking technology. FMNT also inhibits the activation of the NF-κB signaling pathway and microglia in the BLA of mice suffering from chronic inflammatory pain. Therefore, the anxiolytic effects of FMNT are partially due to the attenuation of inflammation and neuronal hyperexcitability through the inhibition of NMDA receptor and CBP in the BLA.

Tetrahydroxystilbene glucoside relieves the chronic inflammatory pain by inhibiting neuronal apoptosis, microglia activation, and GluN2B overexpression in anterior cingulate cortex.

Tetrahydroxystilbene glucoside (THSG) is one of the active ingredients of Polygonum multiflorum. It has been shown to exert a variety of pharmacological effects, including antioxidant, anti-aging, and anti-atherosclerosis. Because of its prominent anti-inflammatory effect, we explored whether THSG had analgesic effect. In this study, we used a model of chronic inflammatory pain caused by injecting complete Freund's adjuvant into the hind paw of mice. We found THSG relieved swelling and pain in the hind paw of mice on a dose-dependent manner. In the anterior cingulate cortex, THSG suppressed the upregulation of GluN2B-containing N-methyl-D-aspartate receptors and the downregulation of GluN2A-containing N-methyl-D-aspartate receptors caused by chronic inflammation. In addition, THSG increased Bcl-2 and decreased Bax and Caspase-3 expression by protecting neuronal survival. Furthermore, THSG inhibited the phosphorylation of p38 and the increase of nuclear factor κB (NF-κB) and tumor necrosis factor α (TNF-α). Immunohistochemical staining revealed that THSG blocked the activation of microglia and reduced the release of proinflammatory cytokines TNF-α, interleukin 1ß (IL-1ß), and interleukin 6 (IL-6). In conclusion, this study demonstrated that THSG had a certain effect on alleviating complete Freund's adjuvant-induced chronic inflammatory pain.

Gentiopicroside protects neurons from astrocyte-mediated inflammatory injuries by inhibition of nuclear factor-κB and mitogen-activated protein kinase signaling pathways.

The effects of gentiopicroside (Gent), an active component derived from the traditional Chinese medicine Gentiana macrophylla, on lipopolysaccharide-induced astrocyte activation and subsequent neuronal damage were investigated. Gent significantly inhibited the release of tumor necrosis factor-α, interleukin-1ß, nitric oxide, and prostaglandin E, as well as expressions of inducible nitric oxide synthase and cyclooxygenase-2 in lipopolysaccharide-induced primary astrocytes. Furthermore, Gent relieved neurotoxicity from astrocyte-mediated inflammatory injury. Mechanism studies indicated that Gent significantly suppressed nuclear factor-κB nuclear translocation and down-regulated c-Jun-N-terminal kinase/stress-activated protein kinase mitogen-activated protein kinase phosphorylation levels with little influence on elevated p-p38 levels. Taken together, our findings suggested Gent could prevent the neurotoxicity related to astrocyte-mediated inflammatory injury by inhibition of nuclear factor-κB and mitogen-activated protein kinase signaling pathways. The study also indicated that neuronal injury could be prevented by promptly modulating inflammatory responses of astrocytes.

Effect of Praeruptorin C on 3-nitropropionic acid induced Huntington's disease-like symptoms in mice.

Huntington's disease (HD) is an autosomal dominant inherited disease characterized by movement, psychiatric, and cognitive disorders. Previous research suggests that Praeruptorin C (Pra-C), an effective component in the root of Peucedanum praeruptorum dunn, a traditional Chinese medicine, may function in neuroprotection. The present study was conducted to evaluate the effectiveness of Pra-C in the treatment of HD-like symptoms in a 3-nitropropionic acid (3-NP) mouse model, and to explore the possible mechanism of the drug's activity. We treated 3-NP-injected mice with two different doses of Pra-C (1.5 and 3.0mg/kg) for 3 days. Motor behavior was tested using the open field test (OFT) and rotarod test, while psychiatric symptoms were tested using the forced swimming test (FST) and tail suspension test (TST). We found that Pra-C alleviated the motor deficits and depression-like behavior in the 3-NP-treated mice, and protected neurons from excitotoxicity. Western blot analysis revealed that Pra-C upregulated BDNF, DARPP32, and huntingtin protein in the striatum of 3-NP mice. These results taken together suggest that Pra-C may have therapeutic potential with respect to the movement, psychiatric, and cognitive symptoms of HD.

Antidepressant-Like and Anxiolytic-Like Effects of ZBD-2, a Novel Ligand for the Translocator Protein (18 kDa).

Activation of translocator protein (18 kDa) (TSPO) plays an important role to mediate rapid anxiolytic efficacy in stress response and stress-related disorders by the production of neurosteroids. However, little is known about the ligand of TSPO on the anxiety-like and depressive behaviors and the underlying mechanisms in chronic unpredictable mild stress (UCMS) mice. In the present study, a novel ligand of TSPO, ZBD-2 [N-benzyl-N-ethyl-2-(7,8-dihydro-7-benzyl-8-oxo-2-phenyl-9H-purin-9-yl) acetamide] synthesized by our laboratory, was used to evaluate the anxiolytic and antidepressant efficacy and to elucidate the underlying mechanisms. ZBD-2 (3 mg/kg) significantly attenuated anxiety-like and depressive behaviors in the UCMS mice, which was blocked by TSPO antagonist PK11195 (3 mg/kg). Treatment of ZBD-2 reversed the decrease in biogenic amines (norepinephrine, dopamine, and serotonin) in the brain region of hippocampus in the UCMS mice. The decreases in TSPO, GluN2B-containing N-methyl-D-aspartate (NMDA) receptors, GluA1, p-GluA1-Ser831, p-GluA1-Ser845, PSD-95, and GABAA-a2 were integrated with the increases of CaMKII and iNOS levels in the hippocampus of the UCMS mice. ZBD-2 significantly reversed the changes of above proteins. However, ZBD-2 or PK11195 treatment did not affect the levels of GluN2A-containing NMDA receptors and the total levels of GAD67. Our study provides strong evidences that ZBD-2 has a therapeutic effect on chronic stress-related disorders such as depression and anxiety through regulating the biogenic amine levels and the synaptic proteins in the hippocampus.

Sinomenine attenuates chronic inflammatory pain in mice.

Sinomenine, an alkaloid originally isolated from the roots of Sinomeniumacutum, is used as a traditional Chinese medicine for rheumatic arthritis. However, little is known about the neuronal mechanisms underlying the analgesic effects of sinomenine in animals with chronic inflammatory pain. In this study, we investigated the persistent inflammatory pain induced by hind paw injection of complete Freund's adjuvant (CFA) in mice, which was reversed by sinomenine administration. In the anterior cingulate cortex (ACC), a region highly associated with chronic pain processing, the upregulation of GluN2B-containing N-methyl-D-aspartate (NMDA) receptors and Ca2+/calmodulin-dependent protein kinase II, total levels of GluA1, and phosphorylation of GluA1 at Ser831 (p-GluA1-Ser831) were reversed by systemically administrating sinomenine. Furthermore, sinomenine treatment downregulated the mammalian target of rapamycin (mTOR) pathway. Increases in p-mTOR, p-p70S6k, p-S6, and p-4EBP, which were induced by chronic inflammation, were all changed. However, sinomenine did not affect the levels of GluN2A-containing NMDA receptors and p-GluA1-Ser845, as well as the total levels of mTOR, p70S6k, S6, and 4EBP. In conclusion, results indicated that sinomenine reduced the chronic inflammatory pain induced by CFA, at least partially by regulating the GluN2B receptors and mTOR signals in the ACC.

Anti-hyperlipidemia and antioxidant activities of Amygdalus pedunculata seed oil.

This study attempts to evaluate the beneficial effects of Amygdalus pedunculata seed oil (AO) on the lipid profile and antioxidant status of high-fat fed rats and d-galactose (d-gal)-induced oxidative mice. The anti-hyperlipidemia effects of AO were evaluated. AO supplementation (2%, 4%, and 8%) for three weeks significantly decreased the total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL) levels and increased the high-density lipoprotein (HDL) levels in the high fat diet rats unlike in the model group. The antioxidant activities of AO were determined in the d-gal-injected mice. Results showed that AO (2%, 4%, and 8%) enhanced the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), as well as lowered the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and malondialdehyde (MAD) in the liver of d-gal-injected mice. Compared with olive oil (OO) and rapeseed oil (RSO), the results of tests indicated that AO lowered the hyperlipidemia risk factors by improving plasma antioxidant defenses and lipid profiles.

Gastrodin relieved complete Freund's adjuvant-induced spontaneous pain by inhibiting inflammatory response.

The analgesic effects of gastrodin (GAS), an active component derived from the Chinese herb Tian ma (Gastrodia elata Blume), on chronic inflammatory pain of mice and the involved molecular mechanisms were investigated. GAS significantly attenuated mice chronic inflammatory pain induced by hindpaw injection of complete Freund's adjuvant (CFA) and the accompanying anxiety-like behaviors. GAS administration reduced CFA-induced up-regulation of GluR1-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, GluN2A- and GluN2B-containing N-methyl-d-aspartate (NMDA) receptors, and Ca2+/calmodulin-dependent protein kinase II-alpha (CaMKII-α) in the anterior cingulate cortex (ACC). The GluN2A and GluN2B subunits of NMDA receptors, the GluR1 type of AMPA receptor, and CaMKII-α are key molecules responsible for neuroplasticity involved in chronic pain and the accompanying anxiety. Moreover, GAS administration reduced the activation of astrocyte and microglia and the induction of TNF-α and IL-6 in the ACC of the CFA-injected mice. Therefore, GAS administration relieved chronic pain, exerted anxiolytic effects by regulating neuroplasticity molecules, and attenuated the inflammatory response by reducing the induction of TNF-α and IL-6 in the ACC of the CFA-injected mice.

Protective Effects of Gastrodin Against Autophagy-Mediated Astrocyte Death.

Gastrodin is an active ingredient derived from the rhizome of Gastrodia elata. This compound is usually used to treat convulsive illness, dizziness, vertigo, and headache. This study aimed to investigate the effect of gastrodin on the autophagy of glial cells exposed to lipopolysaccharides (LPS, 1 µg/mL). Autophagy is a form of programmed cell death, although it also promotes cell survival. In cultured astrocytes, LPS exposure induced excessive autophagy and apoptosis, which were significantly prevented by the pretreatment cells with gastrodin (10 µM). The protective effects of gastrodin via autophagy inhibition were verified by the decreased levels of LC3-II, P62, and Beclin-1, which are classical markers for autophagy. Furthermore, gastrodin protected astrocytes from apoptosis through Bcl-2 and Bax signaling pathway. The treatment of astrocytes with rapamycin (500 nM), wortmannin (100 nM), and LY294002 (10 µM), which are inhibitors of mTOR and PI3K, respectively, eliminated the known effects of gastrodin on the inhibited Beclin-1 expression. Furthermore, gastrodin blocked the down-regulation of glutamine synthetase induced by LPS exposure in astrocytes. Our results suggest that gastrodin can be used as a preventive agent for the excessive autophagy induced by LPS.

Silibinin Prevents Autophagic Cell Death upon Oxidative Stress in Cortical Neurons and Cerebral Ischemia-Reperfusion Injury.

Neuronal apoptosis and oxidative stress are involved in most of the neurodegenerative diseases, promoting neuron survival is critical for therapy. Silibinin (SLB), which is derived from the seeds of Silybinisus laborinum L., has been widely used as an antioxidant. Here we tested the neuroprotective effects of SLB and the involved molecular mechanisms. We demonstrated that SLB promoted neuron viability upon hydrogen peroxide (H2O2) challenge and reduced hypoxia/ischemia injury in the middle cerebral artery occlusion (MCAO) mouse model. SLB reversed the decreased level of procaspase-3 and balanced Bcl-2 and Bax expression upon H2O2 insult to inhibit cell apoptosis. Furthermore, SLB suppressed the activation of autophagy by decreasing microtubule-associated protein 1 light chain 3 (LC3-II) and Beclin-1 levels under oxidative stress accordingly. SLB phosphorylated protein kinase B (Akt-1) at Ser473 in a time- and dose-dependent manner. The inhibitor for phosphoinositide-3-kinase (PI3K) wortmannin abrogated SLB-induced phosphorylation of Akt-1 and mTOR, decreased the suppression of autophagy, and therefore abolished SLB-mediated neuroprotection. All the data suggested that SLB protected neurons by inhibiting both the mitochondrial and autophagic cell death pathways. This study opens new avenues for the use of SLB in treatment of central nervous system (CNS) diseases in which oxidative stress plays a major role in disease pathogenesis. Given that it occurs naturally with low toxicity and pleiotropic effects that benefit the nervous system, SLB acts potentially as a novel therapy for ischemic injury.

Anxiolytic effects of sesamin in mice with chronic inflammatory pain.

OBJECTIVE: Sesamin is known for its role in antioxidant, antiproliferative, antihypertensive, and neuroprotective activities. However, little is known about the role of sesamin in the development of emotional disorders. Here we investigated persistent inflammatory pain hypersensitivity and anxiety-like behaviors in the mouse suffering chronic pain. METHODS: Chronic inflammatory pain was induced by hind paw injection of complete Freund's adjuvant (CFA). Levels of protein were detected by Western blot. RESULTS: Administration of sesamin could induce anxiolytic activities but had no effect on analgesia. In the basolateral amygdala, a structure involving the anxiety development, sesamin attenuated the up-regulation of NR2B-containing N-methyl-d-aspartate receptors, GluR1 subunit of the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor as well as phosphorylation of GluR1 at Ser831 (p-GluR1-Ser831), and Ca(2+)/calmodulin-dependent protein kinase II (CaMKII-alpha) in the hind paw CFA-injected mice. In the same model, we found that the sesamin blocked the down-regulation of gamma-aminobutyric acid A (GABAA-alpha-2) receptors. CONCLUSION: Our findings show that sesamin reduces anxiety-like behaviors induced by chronic pain at least partially through regulating the GABAergic and glutamatergic transmission in the amygdala of mice.

Analgesic effects of NB001 on mouse models of arthralgia.

Our previous studies have demonstrated the critical roles of calcium-stimulated adenylyl cyclase 1 (AC1) in the central nervous system in chronic pain. In the present study, we examined the analgesic effects of NB001, a selective inhibitor of AC1, on animal models of ankle joint arthritis and knee joint arthritis induced by complete Freund's adjuvant injection. NB001 treatment had no effect on joint edema, stiffness, and joint destruction. Furthermore, the treatment failed to attenuate the disease progression of arthritis. However, NB001 treatment (3 mg/kg) significantly weakened joint pain-related behavior in the mouse models of ankle joint arthritis and knee joint arthritis. Results indicated that NB001 exhibited an analgesic effect on the animal models of arthritis but was not caused by anti-inflammatory activities.

Osteoprotective Effect of Echinocystic Acid, a Triterpone Component from Eclipta prostrata, in Ovariectomy-Induced Osteoporotic Rats.

Echinocystic acid (EA) is a natural triterpone enriched in various herbs and has been used for medicinal purposes in China. In the present study, we systematically examined the effects of EA on ovariectomy-induced osteoporosis in rats for the first time. Three-month-old female ovariectomy (OVX) Sprague-Dawley rats were used to evaluate the osteoprotective effect of EA. Results showed that administration of EA (5 or 15 mg/kg/day) for 12 weeks prevented lower levels of maximum stress and Young's modulus of femur induced by OVX. EA also recovered bone metabolic biomarkers levels in OVX rats, including osteocalcin, alkaline phosphatese, deoxypyridinoline, and urinary calcium and phosphorus. EA (5 and 15 mg/kg/day) could prevent the alteration of total bone mineral density in the femur caused by OVX. However, only high dose (15 mg/kg/day) of EA significantly improved trabecular architecture, as evidenced by higher levels of bone volume/tissue volume, trabecula number, and trabecula thickness, and lower levels of trabecula separation and structure model index compared with OVX rats. In addition, EA treatment decresed the serum levels of IL-1ß and TNF-α in OVX rats. In conclusion, EA could prevent reduction of bone mass and strength and improve the cancellous bone structure and biochemical properties in OVX rats. Hence, EA may serve as a new candidate or a leading compound for anti-osteoporosis.