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The Eect of Royal Jelly on Depression and Anxiety in an Animal Model of Alzheimers Disease
Maryam Azimpour1, Mohammad Fathi*2, Omid Dezfoulian3
1Department of Physical Education and Sport Sciences, Faculty of Literature, Lores
tan University, Khorramabad, Iran
2Department of Physical Education, Faculty of Humanities, Lores
tan University, Khorramabad, Iran
3Department of Pathobiology, School of Veterinary Medicine, Lores
tan University, Khorramabad, Iran
*Corresponding Author: Mohammad Fathi
Email: Fathi.m@lu.ac.ir
Keywords:
1. Depression
2. Anxiety
3. Swimming
Introduction: Royal Jelly (RJ) may exert positive eects on the function of the central nervous
sys
tem. The aim of the present s
tudy was to inves
tigate the eect of RJ on depression and
anxiety in trimethyltin (TMT)-induced Alzheimer’s disease (AD) model in rats. Materials
and Methods: 32 rats were randomly divided into four groups; healthy (HC), AD, sham (SH),
and RJ-treated. Forced Swimming Tes
t (FST) for depression and Elevated Plus-Maze (EPM)
for anxiety assessment were performed. Gene expression in the samples was measured using
Real-Time PCR. Results: The dependent variable of immobility signicantly increased in
the AD group compared to the HC and RJ groups. Furthermore, the SH group has shown
greater immobility than the HC group. The antioxidant indexes of superoxide dismutase and
glutathione peroxidase were signicantly greater in the RJ group compared to the SH and
AD groups. These indexes were also higher in the HC group than in the SH and AD groups.
The RJ and HC groups exhibited a signicant reduction in anxiety behaviours compared to
the other groups. Conclusion: RJ supplementation has the ability to modulate the mood in
the TMT model of AD in rats and may exert benecial eects in the treatment of AD.D
ABSTRACT
Article Info:
Received: 28 June 2020 Revised: 29 Nov 2020 Accepted: 14 Dec 2020
[ DOI: 10.52547/shefa.9.2.79 ] [ Downloaded from shefayekhatam.ir on 2022-11-28 ]
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


SHADHC
FSTRJ
EMP

SHRJHCAD
HC
ADSHRJ
ADSHHC
HCRJ
RJ



[ DOI: 10.52547/shefa.9.2.79 ] [ Downloaded from shefayekhatam.ir on 2022-11-28 ]
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








AD






AD

AD




































AD










TMT

    


TMT
CNS






TMT




TMT 
  

1 Dementia
2 Alzheimer›s disease; AD
3 Organotin
4 Trimethyltin chloride; TMT
5 PVC
6 Central nervous sys
tem; CNS
[ DOI: 10.52547/shefa.9.2.79 ] [ Downloaded from shefayekhatam.ir on 2022-11-28 ]
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





TMT



TMT
TMT





HC
TMT
ADC
SHTMT
RJ
RJTMT


Luacra
RJ



mgkg

FST






      




TMT

 






RJRJ


 RJ

       







RJ




RJ

TMT














7 Royal Jelly; RJ
8 Sprag dowley
[ DOI: 10.52547/shefa.9.2.79 ] [ Downloaded from shefayekhatam.ir on 2022-11-28 ]
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









EMP
EMP

















OAE
OAT
GPXSOD










RNA
RBBuer

mercaptoethanol–β

CollectionTube FilterColumn   



RNAElutionTube

cDNA
K
RealtimePCR
β2mAlleleIDv



RNAcDNADNA
PCR
cDNA

DNAPCRRNA

PCR

RealQ2x Mas
ter mix Green DyePCR
AMPLQON


ΔΔCt
9 Elevated Plus Maze
10 Open Arm Entries
11 Open Arm Time
[ DOI: 10.52547/shefa.9.2.79 ] [ Downloaded from shefayekhatam.ir on 2022-11-28 ]
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

    MANOVA 

SODGPX  

OATOAE

B2m






12 Multivariate analysis of variances

[ DOI: 10.52547/shefa.9.2.79 ] [ Downloaded from shefayekhatam.ir on 2022-11-28 ]
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

 





   
   
P>


SOD
 F   GPX OAE OAT
P>
SOD


13 Shapiro-Wilk Tes
t
14 Levene’s Tes
t
15 Pillai’s Trace
16 Wilks’ Lambda
17 Hotelling’s Trace
18 Roy’s Larges
t Root
19 Scheee pos
t hoc tes
t

OATSODGPX
OAE



P>

       




SOD

GPX

OAE

OAT



TMT


RJ


[ DOI: 10.52547/shefa.9.2.79 ] [ Downloaded from shefayekhatam.ir on 2022-11-28 ]
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

TMT
   CNS    



TMTTMT
EMP




TMT









TMT


[ DOI: 10.52547/shefa.9.2.79 ] [ Downloaded from shefayekhatam.ir on 2022-11-28 ]
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




OAEOAT
TMT

OATOAE


TMT















RJ






RJ

TMT










     
  












    




GPXSOD
SODGPX

      
   RJ 
RJ

    


 RJ     
      

  
     




RJ


RJ


[ DOI: 10.52547/shefa.9.2.79 ] [ Downloaded from shefayekhatam.ir on 2022-11-28 ]
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



RJ


     SOD 




RJ

ER


RJ
TMT


     

TMT

TMT


       
RJ
RJ


RJ
AMPN1oxideHDA
 
HDEA
HDEA
BDNF

RJ
  tyr   c  


HDA


AMPRJ
adenosinemonophosphateAMPN1oxide

RJ




RJ

       

RJ

RJ
RJ


RJ
20 Brain-Derived Neurotrophic Factor
21 Tigo
22 Yangming
23 Es
trogen Receptor

in patients with sporadic late-onset Alzheimer's
disease]. Revis
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... RJ consumption led to an improvement in the score of stress together with less favorable findings for depression and anxiety. RJ was shown to possess a mood-enhancing potential in animal models (65)(66)(67)(68). A single clinical trial demonstrated that 800 mg of RJ consumption for 12 weeks improves anxiety in post-menopausal women (28). ...
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Aims There is a paucity of evidence regarding the benefit of royal jelly (RJ) on post-stroke complications in patients with ischemic stroke. To address this knowledge gap, this randomized, triple-blind, placebo-controlled clinical trial was carried out to determine the effects of RJ consumption on post-stroke clinical outcomes. Methods Of 64 eligible ischemic stroke patients (45–80 years), 32 were randomized to the RJ and 32 to the placebo groups and completed a 12-week intervention. The intervention group was advised to receive 1,000 mg of RJ dragee daily after breakfast. Post-stroke complications including cognition, fatigue, mental health, and appetite, along with serum levels of brain-derived neurotrophic factor (BDNF), and mid-upper arm circumference (MUAC) were assessed in groups pre-and post-intervention. Results After 12 weeks of RJ consumption, cognitive function [adjusted mean difference, 4.71; 95% confidence interval (CI), 1.75 to 7.67], serum levels of BDNF (adjusted mean difference, 0.36; 95% CI, 0.05 to 0.67), stress (adjusted mean difference, −3.33; 95% CI, −6.50 to −0.17), and appetite (adjusted mean difference, 1.38; 95% CI, 0.19 to 2.56) were significantly improved. However, the findings for fatigue (adjusted mean difference, −4.32; 95% CI, −10.28 to 1.63), depression (adjusted mean difference, −1.71; 95% CI, −5.58 to 2.16), anxiety (adjusted mean difference, −2.50; 95% CI, −5.50 to 0.49), and MUAC (adjusted mean difference, 0.36; 95% CI, −0.11 to 0.84) were less favorable. Conclusion Findings support the benefits of RJ consumption in improving post-stroke complications and clinical outcomes. Clinical trial registration: https://www.irct.ir/trial/59275, Identifier IRCT20180818040827N4.
... Favorable effects of RJ on neuronal disease has been found to be dose-dependent, so that among the doses of 150, 300 and 450 mg / kg, higher doses had the best effect [30]. Consumption of 100 mg / kg RJ decreased depression and anxiety in rats with Alzheimer's disease [31], while according to another study, despite the favorable effects of RJ at doses of 100 and 200 mg / kg, the dose of 200 mg / kg was more favorable than the dose of 100 mg / kg [32]. In addition, studies that examined the effect of RJ consumption with exercise training showed that the interaction of both interventions improves motor balance, cognitive function, memory and neurotrophins in rats with trimethyltin neurotoxin-induced neurological disorders [24,33]. ...
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Background: Although the beneficial role of training and the use of some antioxidants in physiological and psychological disorders in autoimmune diseases has been reported, the simultaneous effect of aerobic training (AT) and royal jelly (RJ) with different doses is not well understood. The present study aimed to investigate the effect of AT and RJ on inflammatory factors, hippocampus and psychological functions in the experimental autoimmune encephalomyelitis (EAE). Methods: Sprague-Dawley rats with EAE were assigned to seven groups: (1) EAE, (2) sham (Sh), (3) 50 mg / kg RJ (RJ50), (4) 100 mg / kg RJ (RJ100), (5) AT, (6) AT + RJ50, and (7) AT + RJ100 and healthy control. Results: AT decreased IL-17, TGF-β gene expression and immobilization time, while it increased IL-10, OAT% and OAR% compared to the EAE group. RJ50 and RJ100 decreased IL-17, IL-23 gene expression, and immobilization time, and increased IL-10 and OAR% compared to the EAE group. AT + RJ50 and AT + RJ100 decreased IL-17, IL-23, TGF-β, and immobilization time, while increased IL-10 and OAT% compared to the EAE group. The effect of AT + RJ100 on decreasing IL-17, IL-23, immobilization time, increasing TGF-β, IL-10, and OAR% was more favorable than RJ50. Conclusion: AT and RJ improved inflammatory factors and reduced anxiety and depression. The synergistic effect of two interventions, especially using higher doses of RJ were more favorable.
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Objective Royal jelly is a honey bee secretion with beneficial effects on the nervous system. The present study aims to investigate the effects of royal jelly in reducing seizure and anxiety-like behaviors in Syrian rats. Methods This is an experimental study. In the seizure model, 25 male white Syrian rats were randomly divided into five groups: Control, royal jelly 100 mg/kg, royal jelly 200 mg/kg, royal jelly 400 mg/kg, and phenobarbital. After 30 minutes, strychnine was injected to induce seizure in animals. The time of seizure onset, seizure duration, and mortality rate in animals were recorded. In the anxiety model, 35 male white Syrian rats were randomly divided into five groups: Control, royal jelly 50 mg/kg, royal jelly 100 mg/kg, royal jelly 200 mg/kg, and diazepam. Anxiety-like behaviors were examined by using the elevated plus maze (EPM) test. Data analysis was performed using one-way ANOVA, and P<0.05 was statistically significant. Results Royal jelly at doses of 200 and 400 mg/kg delayed the time of seizure onset and reduced the seizure duration compared to the control group (P<0.05). The mortality rate was also reduced after using different doses of royal jelly compared to the control group (P<0.05). Moreover, royal jelly at doses of 50 and 100 mg/kg increased the time spent in the open arms of the EPM platform and the number of entries to the open arms compared to the control group (P<0.05). Conclusion Administration of royal jelly can reduce strychnine-induced seizure and modulate anxiety-like behaviors in rats.
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Estrogen deficiency after menopause is associated with autonomic nervous changes, leading to memory impairment and increased susceptibility to Alzheimer’s disease (AD). Royal jelly (RJ) from honeybees (Apis mellifera) has estrogenic activity. Here, we investigated whether RJ can improve behavior, cholinergic and autonomic nervous function in ovariectomized (OVX) cholesterol-fed rabbits. OVX rabbits on high-cholesterol diet were administered with RJ for 12 weeks. The results showed that RJ could significantly improve the behavioral deficits of OVX cholesterol-fed rabbits and image structure of the brain. RJ reduced body weight, blood lipid, as well as the levels of amyloid-beta (Aβ), acetylcholinesterase (AchE), and malonaldehyde (MDA) in the brain. Moreover, RJ also increased the activities of choline acetyltransferase (ChAT) and superoxide dismutase (SOD) in the brain, and enhanced heart rate variability (HRV) and Baroreflex sensitivity (BRS) in OVX cholesterol-fed rabbits. Furthermore, RJ was also shown to reduce the content of Evans blue and the expression levels of Aβ, beta-site APP cleaving enzyme 1(BACE1), and receptor for advanced glycation end products (RAGE), and increase the expression level of LDL(low density lipoprotein) receptor-related protein 1 (LRP-1) in the brain. Our findings suggested that RJ has beneficial effects in neurological disorders of postmenopausal women, which were associated with reducing cholesterol and Aβ deposition, enhancing the estrogen levels and the activities of cholinergic and antioxidant systems, and ameliorating the blood–brain barrier (BBB) permeability and restoring autonomic nervous system.
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Background: Prenatal stress (PRS) is considered a risk factor for depressive disorder. Adult hippocampal neurogenesis is believed to play a role in the regulation of affective behaviours. GABAergic interneuron is a key modulator in adult hippocampal neurogenesis. Growing evidence indicates that PRS has adverse effects on adult hippocampal neurogenesis and DNA epigenetic modifications of GABAergic system. The aim of this study is to investigate whether epigenetic GABAergic dysfunction participates in the negative impact of PRS on adult hippocampal neurogenesis and -related emotional behaviors. Methods: Behavioral tests were used to explore PRS-induced depression-like behaviors of adult female mice. Immunohistochemistry staining, real-time RT-PCR, western blot and ChIP were employed to detect adult neurogenesis and epigenetic changes of GABAergic system in the hippocampus of PRS mice. Results: PRS mice developed a depression phenotype accompanied by the inhibited maturation of hippocampal newborn neurons. Compared with control mice, PRS mice showed a decreased expression of glutamic acid decarboxylase 67 (GAD67) at the mRNA and protein levels. GABAA receptor agonist phenobarbital could rectify the decrease of BrdU+/NeuN+ cells in PRS mice. PRS mice also showed an increased expression of DNA methyltransferase 1 (DNMT1) and an increased binding of DNMT1 to GAD67 promoter region. The treatment with DNMT1 inhibitor 5-aza-deoxycytidine restored the decrease of BrdU+/NeuN+ cells and depression-like behaviors in PRS mice via improving GABAergic system. Conclusions: The present results indicate that epigenetic changes of GABAergic system are responsible for adult hippocampus neurogenesis and depression-like behaviors in PRS mice.
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Current evidence supports the idea that neural plasticity is a potential cause of depression. Abundant studies indicate that CRMP2 has important roles in neural plasticity. Moreover, CRMP2 may contribute to the etiology of depression. However, the regulatory mechanisms underlying the role of CRMP2 remain unclear. DNA methylation alteration is generally acknowledged to be involved in the development of depression. The aim of this study was to explore the relationship between the expression and DNA methylation of CRMP2 in the hippocampus and prefrontal cortex of a rat depression model. Chronic unpredictable mild stress (CUMS) was used to establish a rat depression model, and body weight and behavioral tests were used to evaluate the effects of stress. Real-time PCR and Western blotting were used to test CRMP2 mRNA and protein expression, respectively, in the hippocampus and prefrontal cortex of rats. DNA methylation levels of the CRMP2 promoter were analyzed by bisulfite sequencing PCR (BSP). CUMS caused depressive-like behavior in rats, as evidenced by: decreased body weight and sucrose preference rate; decreases in the total distance traveled, rearing frequency, velocity, and duration in the center in the open field test (OFT); and prolonged immobility in the forced swimming test (FST). CRMP2 mRNA and protein expression in the hippocampus and prefrontal cortex were significantly decreased in the CUMS group compared with the control group. The levels of CRMP2 promoter DNA methylation in the hippocampus of the CUMS group were significantly higher than those of the control group, while these changes were not observed in the prefrontal cortex of CUMS rats. Our data provide evidence that altered expression of CRMP2 in the hippocampus and prefrontal cortex is associated with the pathogenesis of depression. Moreover, the results also suggest regional differences in the regulation of DNA methylation in the CRMP2 promoter between the hippocampus and prefrontal cortex during the development of depression.
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As important components of positive and negative reinforcement, locomotor sensitization and withdrawal anxiety following repeated exposure to nicotine (NIC) constitute crucial risk factors for relapse to NIC use after abstinence. Glycyrrhiza radix (G. radix), an important tonic used in traditional Oriental medicine, has not only anxiolytic effects but also reduces NIC-induced locomotor sensitization. Isoliquiritigenin (ISL), a bioactive ingredient of G. radix, also exhibits neuropharmacological effects, including anxiolytic action. Previously, we reported that ISL suppressed cocaine-induced extracellular dopamine release in the nucleus accumbens shell (NaccSh) and attenuated methamphetamine-induced neurotoxicity. The present study was performed to evaluate the effects of ISL on both NIC withdrawal anxiety and locomotor sensitization. Adult male rats received subcutaneous administration of NIC hydrogen tartrate (0.4 mg/kg, twice a day) for 7 days followed by 4 days of withdrawal. During the period of NIC withdrawal, the rats received four intragastric treatments with ISL (3, 10, or 30 mg/kg/day). All three doses of ISL significantly inhibited NIC withdrawal-induced anxiety-like behaviors in the elevated plus maze (EPM) test, but only the 10 mg/kg/day and 30 mg/kg/day ISL doses attenuated locomotor sensitization induced by a challenge dose of NIC. Intracerebroventricular ISL also inhibited both NIC-induced withdrawal anxiety and locomotor sensitization, but intra-NaccSh injection of ISL blocked only NIC locomotor sensitization, which was abolished by post-ISL infusion of tert-butyl hydroperoxide (an oxidant) or N-methyl-D-aspartate (NMDA) into the NaccSh. Moreover, there was increased protein expression of phosphorylated Erk1/2 in the NIC-sensitized NaccSh, which was suppressed by ISL. Taken together, these results suggest that ISL can inhibit repeated NIC-induced withdrawal anxiety and locomotor sensitization, and the latter is mediated by antagonizing accumbal reactive oxygen species and NMDA receptor signaling. 1. Introduction Tobacco smoking is strongly linked to respiratory disease, cardiovascular disease, diabetes mellitus, and various cancers, and despite a great deal of effort, attempts to quit smoking often end in failure due to nicotine (NIC) dependence [1]. Accordingly, treatment of NIC dependence has become the key factor in quitting smoking. However, with the exception of NIC receptor-based replacement therapies and bupropion, which have shown limited effectiveness [2], no effective pharmacological interventions have yet been reported to aid in overcoming NIC dependence, highlighting the need to develop new pharmaceutical candidates for this purpose. NIC is strongly addictive, which is sustained by both positive (rewarding effects) and negative reinforcement (withdrawal symptoms). Like other psychostimulants, NIC acts on the mesolimbic dopamine system leading to an increase in dopamine release in the nucleus accumbens shell (NaccSh) to produce rewarding effects, which are behaviorally manifested by increased locomotor activity in rodents, and the higher locomotor activity usually reflects the potency of the reward effect [3, 4]. Repeated NIC exposure escalates locomotor activity in rats; particularly, a challenge dose of NIC evokes much more enhanced locomotor response after withdrawal, a phenomenon referred to as locomotor sensitization [4, 5]. This behavioral sensitization appears to mimic the heightened smoking euphoria after some period of abstinence in smokers and serves as a behavioral marker for the positive reinforcement in NIC dependence and is useful in screening possible pharmacological agents for NIC dependence. Similar to other major drugs of abuse, abstinence from repeated NIC treatment produces somatic and affective withdrawal symptoms, such as gastrointestinal discomfort, bradycardia, irritability, anxiety, and depression [6], which construct the source of negative reinforcement, driving abstinent smokers to relapse to smoking to relieve the withdrawal discomfort [7]. Among the NIC withdrawal symptoms, anxiety has been identified as the greatest concern because it is the most common withdrawal symptom in abstinent smokers [8] and has been well established in a variety of animal models [9]. Therefore, pharmacologically preventing or relieving anxiety during NIC withdrawal is a promising way to help smokers to quit. Repeated NIC exposure causes adaptive alterations in the reward circuits to change the patterns of physiological responses to internal and external stimuli, such as augmented response to a challenge dose of drugs of abuse, decreased reward neurotransmission [10], and elevated activities of the stress systems, which underlie both the sensitized behavioral response and withdrawal syndrome [3, 11]. These allostatic changes involve diverse brain reward circuits, fundamentally taking place at the level of neurotransmitters, which ultimately become the targets for pharmacotherapies [3, 12]. Elevated glutamatergic transmission in the NaccSh during NIC withdrawal contributes to both positive [13] and negative reinforcement [9, 14, 15]. Recent evidence has indicated that increased levels of reactive oxygen species (ROS) by repeated exposure to drugs of abuse in several brain regions, including the NaccSh, are also involved in NIC behavioral sensitization [5] and withdrawal anxiety [16]. These findings indicate that bioactive agents that can concurrently antagonize central glutamatergic transmission and oxidative stress represent optimal candidates for pharmacotherapies for NIC dependence. Glycyrrhiza radix (G. radix) is historically used in the treatment of various injuries and detoxification in traditional Oriental medicine due to its well-known anti-inflammatory and antioxidative properties [17], and animal studies over the past two decades have shown that G. radix also has neuropharmacological properties, such as neuroprotection and sedation [18]. Especially, G. radix was shown to have therapeutic effects on psychostimulant dependence. G. radix suppressed acute cocaine-induced dopamine release in the NaccSh [19], inhibited methamphetamine-induced locomotor sensitization in rats [4], and blocked NIC-induced locomotor sensitization by counteracting accumbal oxidative stress [5]. G. radix contains various flavonoids and pentacyclic triterpene saponins as the major bioactive constituents, including liquiritigenin, isoliquiritigenin (ISL), liquiritin apioside, and glycyrrhizin [17]. Among these constituents, accumulating evidence suggests that ISL is responsible for the effects of G. radix on drug dependence, as ISL shares almost the same pharmacological spectrum with G. radix [20]. For example, both were shown to inhibit acute cocaine-induced accumbal dopamine release in the same study [19] and exhibited anxiolytic effects in rats [21, 22]. Similar to G. radix, ISL exerts neuroprotective effects via its antioxidant actions [5, 23]. Moreover, ISL is an important phytochemical that antagonizes glutamatergic N-methyl-D-aspartate (NMDA) receptors, which improved glutamate-induced cell death of primary cultured rat cortical neurons [24, 25]. Our previous studies also showed that ISL protected against methamphetamine-induced neurotoxicity in the striatum of mice via suppression of glial cell activation [26]. Taken together, these observations suggest that ISL may inhibit both the positive and negative reinforcement induced by repeated NIC use, suggesting its potential for the treatment of NIC dependence. To examine this possibility, we evaluated the effects of ISL on both repeated NIC-induced withdrawal anxiety and locomotor sensitization in rats and investigated the underlying mechanisms with a focus on the NaccSh. 2. Materials and Methods 2.1. Reagents ISL was provided by Shanghai Yuanye Biotechnology Co., Ltd. (Shanghai, China). (−)-Nicotine hydrogen tartrate, tert-butyl hydroperoxide (t-BOOH), and NMDA were purchased from Sigma-Aldrich (St. Louis, MO, USA). Primary antibodies against total extracellular regulated protein kinases 1/2 (Erk1/2), phospho (P)-Erk1/2, and β-actin were obtained from Abcam (Cambridge, UK), and horseradish peroxidase-conjugated secondary antibody was purchased from Cell Signaling Technology (Beverly, MA, USA). 2.2. Animals and Experimental Protocols Nine-week-old male Sprague Dawley rats (280–300 g) were provided by the Laboratory Animal Center at Qiqihar Medical University (Qiqihar, China). The rats were caged three to a group with free access to food and water in an environment with filtered pathogen-free air at a temperature of 21–23°C and relative humidity of 50%, with a 12 : 12 hour light/dark cycle. All experimental procedures adhered to the National Institutes of Health Guide for the Care and Use of Laboratory Animals and were approved by the Animal Care and Use Committee of Qiqihar Medical University (approval number: QMU-AECC-2016-16). To induce NIC withdrawal, a cohort of rats received subcutaneous injection of 0.4 mg/kg nicotine hydrogen tartrate dissolved in saline (pH 7.2; equal to 0.14 mg/kg NIC free base) twice a day for 7 days in their home cages followed by 4 days of withdrawal. During the NIC withdrawal period, the rats were given ISL intragastrically (3, 10, or 30 mg/kg/day, dissolved in 5% Tween-80) or vehicle once a day for 4 days. At 30 min after the final dose of intragastric ISL, the rats were checked in the elevated plus maze (EPM) paradigm to evaluate anxiety-like behaviors. The experimental groups for evaluating anxiety-like behaviors were as follows: (1) Saline/Vehicle (5% Tween-80) (n = 8); (2) NIC/Vehicle (n = 8); (3) NIC/ISL03 (3 mg/kg ISL) (n = 8); (4) NIC/ISL10 (n = 8); and (5) NIC/ISL30 (n = 8). 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