Objectives: Obesity and the associated metabolic dysfunction influence fertility performance at molecular levels and ABC transporters are considered as potential molecular factors affecting fertility both in the testis and sperm; therefore, we aimed to examine the effect of a short-term diet-induced obesity on testicular and spermatic ABC transporters in a rat model focusing on the expressions of P-glycoprotein (P-gp, Abcb1) and breast cancer resistance protein (BCRP, Abcg2). The testicular androgen state involving aromatase enzyme (Cyp19a1), androgen receptor (Ar), and testosterone levels were also evaluated. Methods: Obesity was induced in male Sprague Dawley rats by feeding a high-fat, high-sugar diet (HFHSD) for 10 weeks, and metabolic status was evaluated using a glucose tolerance test. The weight and size of reproductive organs were measured, and Abcb1a/1b, Abcg2, Cyp19a1, and Ar expression in testes or sperm was determined by RT-PCR and Western blotting. At the same time, testosterone levels were measured by ELISA. Results: HFHSD successfully induced higher weight gain with glucose intolerance and reduced reproductive organ size. In obese rats, testicular Abcb1a and Abcb1b mRNA and P-gp protein expression were significantly higher, whereas testicular Abcg2 mRNA levels decreased. Spermatic Abcb1a, Abcb1b and Abcg2 mRNA expression also reduced in obesity. Neither testicular testosterone concentration nor Cyp19a1 and Ar mRNA expression levels changed after the 10-week obesogenic diet compared with controls. Conclusions: Overall, our study revealed infertility-related ABC transporter changes in obese male rats, suggesting that these alterations may predispose obese males to fertility impairments, even before the obesity-induced androgen dysregulation.

Background: Calonysterone (CAL) is a natural derivative of 20-hydroxyecdysone (20E) with enhanced bioactivity on skeletal muscle cells in vitro, but its in vivo physiological actions remain less well characterized. This study aimed to compare the effects of 20E and CAL on metabolic, muscular, and endocrine parameters in normal and obese male rats, with a particular focus on androgen balance. Methods: Male rats were treated with 20E or CAL under normal (ND) or high-fat, high-sugar dietary (HFHSD) conditions for 12 weeks. Body weight, food intake, skeletal and androgen-sensitive muscle mass, and testicular weight were measured. Testicular expression of androgen receptor (Ar) and aromatase (Cyp19a1) mRNA was assessed by RT-PCR. ELISA was used to determine the plasma corticosterone, testosterone and ERβ level in testes. Results: 20E and CAL prevented HFHSD-induced weight gain and skeletal muscle atrophy. CAL uniquely preserved testicular and levator ani muscle mass in obese rats. CAL increased the expression of Cyp19a1 and ERβ in testicles. Decreased Ar mRNA expression was regulated in 20E- and CAL-treated obese animals. While 20E treatment significantly reduced plasma testosterone levels in the normal diet group compared to controls, both 20E and CAL interventions elicited significant reductions in the obese group relative to both the ND and HFHSD groups. HFHSD-induced increase in plasma corticosterone levels was normalized by 20E or CAL treatment. Conclusions: 20E and CAL exhibit beneficial metabolic and anabolic effects by preventing HFHSD-induced obesity and consequential muscle atrophy. CAL counteracts obesity-induced testicular atrophy in terms of tissue mass. Based on our results, we hypothesized that CAL enhances testicular aromatase levels, which may lead to increased compensatory androgen receptor mRNA expression and increased ERβ levels. These complex, not yet fully understood results underscore the need for caution in the use of phytoecdysteroids as dietary supplements.

AIMS:Our objective was to measure the effect and mechanism of action of the melatonin agonist ramelteon in rat uteri from non-pregnant and pregnant rats in vitro. MAIN METHODS:KCl-induced contractions of non-pregnant and pregnant uterine rings samples (whole or endometrium-denuded) were investigated in an organ bath in the presence of ramelteon alone or with melatonin (MT) receptor antagonist luzindole or with the high-conductance calcium-dependent potassium channel (BKCa) blocker paxilline. The changes in melatonin receptor expressions were followed by RT-PCR, Western blot, and fluorescent immunohistochemistry. KEY FINDINGS:Ramelteon inhibited uterine contractions, with the degree of inhibition being greater towards the end of pregnancy. Both MT1 and MT2 receptors were identified in all uteri (except gestational day 5); they do not participate in the relaxing effect of ramelteon in non-pregnant and 5-day pregnant samples. The activation of BKCa appears to be a constitutive component of the uterorelaxant action of ramelteon throughout the gestational period. Endometrial melatonin receptors have a significant impact in mediating relaxation in mid- and late pregnancy. SIGNIFICANCE:Ramelteon has a relaxing effect on mid- and late-pregnant uteri through at least a dual mechanism of action. The alteration of melatonin receptors during the gestational period raises the possibility that melatonin receptors might be potential drug targets for the treatment of premature labour.

Pulmonary administration offers a promising needle-free approach for systemic delivery of nonsteroidal anti-inflammatory drugs (NSAIDs), improving bioavailability and reducing required doses. While mannitol and leucine are widely used in inhalation formulations, their potential to enhance systemic drug delivery via the pulmonary route remains largely unexplored. This study utilizes the nanocrystal agglomerates (NCAs) approach to develop an inhalable NSAID formulation, with ketoprofen (KTP) as a model drug. Wet media milling and nano spray drying were employed for NCA fabrication, and the roles of mannitol and leucine were evaluated individually and in combination. Notably, their combination exhibited synergy, overcoming limitations observed with individual excipients. Mannitol-based sample (K1M) reduced aerosol performance by increasing the mass median aerodynamic diameter (MMAD) to 4.5 µm, whereas leucine-based sample (K1L) improved aerosolization but resulted in a low MMAD (<1 µm), suggesting a high tendency for exhalation. The combined mannitol-leucine formulation (K1ML) achieved optimal aerosol performance, balancing dispersibility and controlled deposition. K1ML also exhibited the fastest drug release (99 % in 5 min) and enhanced permeability across the alveolar barrier while maintaining biocompatibility. Pharmacokinetic analysis confirmed that inhaled K1ML provided superior bioavailability (AUC 73 µg·h/mL) compared to oral KTP nanosuspension (42 µg·h/mL) and raw KTP (9 µg·h/mL). Nonetheless, prolonged inhalation in asthmatic models (ovalbumin-sensitised rats) impaired pulmonary function, emphasizing the need for dose optimization. These findings demonstrate that the mannitol-leucine combination in NCAs enhances systemic NSAID delivery, optimizing both aerosol performance and bioavailability. Future studies should refine dosing strategies to ensure long-term safety and clinical feasibility.

Obesity affects approximately 30% of pregnancies worldwide and is one of the leading metabolic disorders among pregnant women. Maternal obesity is often associated with placental dysfunction and structural alterations, which increase the risk of developing complications. Efflux transporters, including P-glycoprotein (P-gp), may impact placental function and fetal development. Consequently, our research examined the effects of obesity on P-glycoprotein expression in both a rat model and human placental tissue. P-gp expression was measured by RT-PCR and Western blot techniques in human and rat placental tissues. Moreover, we further characterized the high-fat and high-sugar diet (HFHSD)-induced gestational obesity rat model by measuring tissue weights. Significant decreases were observed in fetal, placental, and uterus weights in the obese animals near the end of pregnancy. In obese rats, mRNA and protein expression of placental P-gp showed a reduction on gestation days 15, 20, and 22. A similar P-gp reduction was observed in the term placenta in obese women in mRNA and protein levels. We hypothesize that the reduced expression of P-gp may heighten the susceptibility of both the fetus and placenta to P-gp substrates. This alteration could potentially result in an increased risk of pregnancy complications and obesity-related drug contraindications linked to P-gp transport during pregnancy.

Ovulation is a critical event in mammalian reproduction, a complex process that involves the release of a mature oocyte from the ovaries for fertilization. Hormonal shifts are the driving force of the ovulation cycle; however, several other factors are able to fine-tune the occurrence of follicular rupture. Prior to the follicular rupture, the pre-ovulatory luteinizing hormone (LH) surge triggers a self-generating local inflammatory and redox cascade, which is responsible for the release of several inflammatory and redox signaling mediators. Eicosanoids are one of the key regulators of the initiation of the local inflammation within the follicle, while the balance of reactive oxygen species and antioxidants is fundamental to maintaining the physiologically coordinated redox state during the ovulation process. In this review, we aim to provide a summary of the human menstrual and rat estrus cycles and demonstrate the LH-induced inflammatory and redox cascade involved in follicle rupture through the details of lipid-derived and redox signaling mediators.

Globally, the incidence of obesity among adults has significantly risen since 1990, with a more than twofold rise in prevalence. Similarly, the incidence of obesity among adolescents has increased fourfold. Overweight constitutes a significant health and social issue in developed nations globally. Conventional therapies such as lifestyle modification (nutrition and physical activity) have limited weight reduction. Drug therapy is often not possible or cannot be afforded due to poor patient compliance or therapeutic side effects.20-hydroxyecdysone (20E) is a worldwide used ‘green anabolic’ dietary supplement that has beneficial effects in some animal models of metabolic diseases. Our ongoing research examines the impacts of 20E and calonysterone (CAL) in an animal model with a diet high in fats and sugars (HFHSD).Glucose tolerance tests assessed prediabetic status and RT-PCR and western blot analysis determined interleukin-6 (IL6) expression. The concertations of superoxide dismutase, catalase, adiponectin, leptin, and IL-6 were quantified by ELISA. Total antioxidant capacity was assessed using a colorimetric assay kit, and global DNA methylation was also measured.CAL entirely prevented HFHSD-induced obesity and decreased the inflammatory cytokine (IL6) level and antioxidant activity in our model. Both 20E and CAL normalized the changed plasma concentration of adiponectin and leptin after the HFHS diet. The administration of CAL and 20E in obese rats significantly increased the percent of total DNA methylation.This is the first in vivo study on this natural ecdysteroid, which may offer new alternatives for treating metabolic diseases. Based on our findings, we are supposed to show new preventive possibilities for overweight-induced chronic progressive diseases.

IntroductionGenerally, the pregnant women with schizophrenia have higher consumption of medicinal drugs. During pregnancy, placental ABC transporters regulate drug disposition and are involved in fetal and placental development. This study examined the expression and function of placental P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) transporters in vivo and evaluated the epigenetic impact of schizophrenia on the placenta in a rat model.MethodsThe expression of placental P-gp and BCRP was measured by RT-PCR and Western blot techniques in schizophrenia-like Wisket and control Wistar rats on gestation days 15, 18, 20, 21, and 22, while the histone acetyltransferase activity and global methylation state of the placenta were detected by colorimetric kits. Fexofenadine was administered per os (10 mg/kg) to pregnant rats and plasma concentrations of fexofenadine were determined with HPLC analysis on the 21 and 22 days of gestation.ResultsReduced placental P-gp expression was identified in late pregnancy, while the placental BCRP expression upregulation was observed before term in schizophrenia. Significantly lower fetal fexofenadine plasma concentration was measured on the 21st and 22nd days of pregnancy compared to the mother; in contrast, the fexofenadine concentration was similar in the schizophrenia-like mother and fetus. Decreased placental histone acetyltransferase activity and DNA hypermethylation were revealed before term in schizophrenia-like rats.ConclusionBased on our results, we can conclude that the expression and function of the placental efflux proteins we examined are altered in schizophrenia, and possibly as a result, altered substrate concentrations were measured in the fetuses. We hypothesize that the altered protein expression may also be a result of the disease-induced epigenetic pattern changes. This study presents novel disease-associated placental ABC transporter alterations, which highlights the dangers of using transporter substrates, especially P-gp, during pregnancy.

Background: Obesity and gestational diabetes mellitus (GDM) are the most common metabolic conditions that have an unfavorable impact on maternal and fetal health. Maternal obesity and GDM are often associated with placental dysfunction and structural alterations. The apelin receptor (APLNR), vascular endothelial growth factor (VEGF), leptin, and DNA methylation play crucial roles in placental function. We aimed to investigate the placental volume and vascularization, and to determine the changes in these markers in obese and GDM mothers. Material and Methods: In our study, we investigated the human placenta (n = 48) at term. The placental structural analyses on volume and vascularization were conducted using three-dimensional ultrasound before labor. Placental APLNR expression was determined using RT-PCR, and leptin and VEGF concentrations using ELISA in placental tissues. Global DNA methylation was measured using colometric assay. Results: The age of GDM mothers was significantly higher than that of normal and obese mothers. The gestation length of GDM mothers was significantly shorter than that of normal and obese mothers. The placental volume was significantly higher in obese and GDM cases compared with normal cases. Vascularization indices (VI, FI, VFI) were significantly depressed in GDM and obesity. In the case of biomarker studies, APLNR, leptin, and VEGF showed similar decreases in obese and GDM placentas. Based on our results, the effect of GDM, not obesity, was more pronounced for these biomarkers. VEGF reduction correlates with three-dimensional placental vascularity studies. The DNA methylation was significantly elevated in both GDM and obese placental samples, while the GDM effect was more pronounced. Conclusions: This study is the first to demonstrate structural alterations of the placenta using placental tissue biomarkers in obesity and gestational diabetes mellitus (GDM). We found that both GDM and obesity affect placental volume and vascularity, as indicated by reduced leptin and VEGF levels, presumably mediated by epigenetic effects. Our findings may provide a novel therapeutic target for improving abnormal placental function caused by GDM and obesity.

This study aimed to characterize the triple-hit schizophrenia-like model rats (Wisket) by the assessment of (1) behavioral parameters in different test conditions (reward-based Ambitus test and HomeManner system) for a prolonged period, (2) cerebral muscarinic M1 receptor (M1R) expression, and (3) the effects of olanzapine treatment on these parameters. Wistar (control) and Wisket rats were injected for three consecutive weeks with olanzapine depot (100 mg/kg) and spent 4 weeks in large cages with environmental enrichment (HomeManner). The vehicle-treated Wisket rats spent longer time awake with decreased grooming activity compared to controls, without changes in their active social behavior (sniffing, playing, fighting) obtained in HomeManner. Olanzapine treatment decreased most of these parameters, only the passive social interaction (huddling during sleeping) enhanced mostly in the Wisket rats on the injection day, which recovered within 4 days. In the Ambitus test, vehicle-treated Wisket rats showed lower locomotor and exploratory activities and impaired cognition compared to control rats, deteriorating by olanzapine in both groups. In Wisket brain samples, the M1R mRNA expression was significantly lower in the cerebral cortex and elevated in the hippocampus, with no difference in the prefrontal cortex versus control. Olanzapine normalized the hippocampal M1R expression, but enhanced it in the prefrontal cortex. The triple-hit Wisket model rats had impaired behavioral characteristics in both acute reward-based test and undisturbed circumstances investigated for prolonged periods, and altered cerebral M1R expression. Chronic olanzapine treatment resulted deterioration of some parameters in control group, and could restore only few negative signs in model rats.

The limited efficacy of antipsychotics in treating the negative and cognitive symptoms of schizophrenia has prompted the exploration of adjuvant therapies. Several drugs developed for other indications-including caffeine, metformin, and furosemide-have shown procognitive potential. This study evaluated the effects of these agents on behavioral parameters using the reward-based Ambitus test, and on the cerebral D2 dopamine receptor (D2R) expression and binding. The drugs were administered individually and in combination in a schizophrenia-like triple-hit animal model (Lisket rats), derived from the Long Evans (LE) strain. Lisket rats received 14 days of drug treatment via drinking water; water-drinking LE rats served as the controls. The Ambitus test was conducted before treatment and on days 11-14. Caffeine enhanced activity without affecting learning or memory. Metformin and furosemide reduced exploratory behavior but improved reference memory; these effects were inhibited by caffeine co-administration. Although no statistically significant behavioral differences were found compared to water-treated Lisket rats, a trend toward reduced exploratory visits was observed in the triple-combination group. Lisket rats exhibited moderately reduced D2R binding in the cortex and increased binding in the hippocampus. Caffeine alone and in combination enhanced hippocampal D2R binding, while furosemide increased cortical D2R expression. This study is the first to highlight the behavioral and molecular effects of these non-antipsychotic agents in a schizophrenia model, supporting their potential for adjunctive use.

Pregnancy presents specific metabolic demands, and disruption caused by a high-fat high-sugar diet (HFHSD) have been associated with significant complications, including maternal health risk, fetal developmental issues, and infertility. Obesity-related changes in the uterine tissues may contribute to these challenges. This study analyzed structural changes in the uterus and adipose tissue of pregnant rats on gestation day 22 fed an HFHSD using various staining techniques. Hematoxylin and eosin staining showed morphological changes in the adipose tissue and the uterine structure, including the lumen size and the thickness of the myometrium, endometrium, and perimetrium. The amount of collagen in the uterus was determined by PicroSirius red staining, while PAS-D staining was used to observe glycogen content. Key protein expressions, such as insulin and leptin receptors and UCP1 and UCP3, were analyzed by immunohistochemistry. The HFHSD promoted hypertrophy of visceral and gonadal adipocytes, suggesting metabolic alterations. By the end of pregnancy, a significant reduction in uterine lumen size was observed. Additionally, a decrease in insulin and higher leptin receptor expressions in the myometrium indicated significant physiological alteration. These findings offer insight into how an HFHSD affects uterine structure and function during late pregnancy but should be interpreted within the physiological context of gestation-related metabolic changes. Further research is needed to understand the functional consequences of these alterations on reproductive and metabolic health.

Maternal obesity and gestational diabetes mellitus (GDM) are the most common metabolic conditions with have unfavourable impact on maternal and fetal health. Key biosubtrats such as apelin, vascular endothelial growth factor (VEGF), leptin, and DNA methylation play crucial roles in these pathologic conditions. Apelin is a peptide involved in regulating glucose metabolism and cardiovascular functions. This molecule also interacts with the apelin receptor to enhance glucose uptake, suggesting potential therapeutic implications for managing GDM and obesity. Leptin, a hormone predominantly produced by adipose tissue, regulates appetite and energy balance. In obesity, leptin levels are often high, but a resistance to its effects develops, disrupting normal metabolic processes. Similarly, in GDM, elevated leptin may impair glucose metabolism and contribute to insulin resistance. VEGF is critical for angiogenesis, the formation of new blood vessels, and is often found in increased concentrations in obese individuals and those with GDM. This elevation may contribute to abnormal placental function and vascular complications, exacerbating both conditions. DNA methylation, an epigenetic modification, plays a crucial role in gene expression regulation. In both GDM and obesity, altered DNA methylation patterns have been observed, affecting genes involved in metabolism, inflammation, and insulin sensitivity. These epigenetic changes may predispose individuals to metabolic disorders. In our study we investigated placental apelin, leptin, VEGF, and DNA methylation interconnection in the pathophysiology of GDM and obesity during gestation. They have similar or different influencing on metabolic regulation, vascular function, and gene expression in GDM and obesity? Sonogpahic examinatios supported the metabolic analyses for that understanding their roles may lead to better management and therapeutic strategies for these conditions.

Aquaporins (AQPs) are involved in the process of implantation, regulate myometrial contractions and cervical ripening, and maintain appropriate placental functioning. The molecular mechanism of these functions is not fully understood. Our study aimed to investigate the physiological significance of AQP5 during pregnancy and to determine the cooperation between the adrenergic system and the AQP5 in uterine contraction in the late-pregnant rat uterus.After administering AQP5 siRNA intraperitoneally to Sprague-Dawley rats, the length of the gestational period was determined and the changes in uterine contractions were measured in an isolated organ bath system. Pharmacological influence on AQP5 expression and uterine contraction was investigated by treatment with terbutaline (10 mg/kg, subcutaneously) and doxazosin (5 mg/kg, orally) in vivo; and mercuric chloride (HgCl2), in vitro. Moreover, the levels of cAMP response element binding protein (CREB) were measured in the uterus by an ELISA kit.The gestational period became shorter, AQP5 expression significantly decreased and rat uterus contraction increased after AQP5 siRNA treatment compared to the control. Treatment with terbutaline significantly increased AQP5 mRNA and protein expression after 30 min and continuously reduced it until 90 min, whereas doxazosin treatment did not significantly alter AQP5 expression. Treatment with the AQP5 antagonist HgCl2 increased spontaneous uterus contraction and decreased norepinephrine-induced uterus contraction with decreasing AQP5 expression in pregnant rat uterus. Moreover, the tocolytic effect through the adrenergic system was amplified in the presence of an AQP5 antagonist, presumably via the changes in cAMP level.In conclusion, our findings elucidate the collaborative role of aquaporin 5 (AQP5) and adrenergic systems in the regulation of uterine contractions in late-pregnant rats. Our findings suggest this may be a good starting point for developing a new tocolytic therapy.

Type 2 diabetes is a chronic disease requiring comprehensive pharmacological and non-pharmacological interventions to slow its progression and prevent or delay its micro- and macrovascular complications. Oxidative stress contributes to the development and progression of type 2 diabetes as well as to the development of its complications through several mechanisms. Therefore, therapeutic targeting of oxidative stress could aid in managing this disease and its complications. In our study, we have collected information on the most frequently used antidiabetic drugs (metformin, glucagon-like peptide 1 receptor agonists and sodium-glucose cotransporter 2 inhibitors) in the EU and the USA based on their antioxidant effects.Based on our results, we can conclude that the antioxidant effects of the investigated antidiabetics may contribute significantly to the management of the disease and its complications and may open new therapeutic perspectives in their prevention.

Background: Obesity and overweight are also becoming more prevalent among women of childbearing age and pregnant women. In maternal obesity, the activation of metabolic, inflammatory, and oxidative stress pathways is proven, which appears to be a key step in the pathological changes observed in placental and uterine function. Several recent studies have evidenced that aquaporins (AQPs) are critical players in adipose tissue biology and are involved in the onset of obesity. Methods: Our studies aimed to investigate the changes in placental volume and vascularization and measure the AQP5 expression and total antioxidant capacity (TAC) in the placenta and uterus tissues in obese and typical-weight mothers. We also aim to measure the AQP5 plasma concentration. Results: We found AQP5 dominance in the uterus and plasma at 34 weeks of normal pregnancy. The placental volume increased and the vascularization decreased in obese mothers compared to the control. The AQP5 expression increased in the uterus of the obese group and did not change in the placenta. The TAC decreased in the plasma of overweight mothers. Conclusions: We hypothesize that increased AQP5 expression prolongs the length of pregnancy and inhibits the onset of contractions. Based on our findings, we can develop diagnostic tests and provide new targets for tocolytic drug development.

In our present series of experiments, we investigated the nasal applicability of the previously developed Soluplus (R) - meloxicam polymeric micelle formulation. Utilizing the nasal drug investigations, moderately high mucoadhesion was experienced in nasal conditions which alongside the appropriate physicochemical properties in liquid state, contributed to rapid drug absorption through human RPMI 2650 cell line. Ex vivo studies also confirmed that higher nasal mucosal permeation could be expected with the polymeric micelle nanoformulation compared to a regular MEL suspension. Also, the nanoformulation met the requirements to provide rapid drug permeation in less 1 h of our measurement. The non-toxic, non-cell barrier damaging formulation also proved to provide a successful passive transport across excides human nasal mucosa. Based on our in vivo investigations, it can be concluded that the polymeric micelle formulation provides higher meloxicam transport to the central nervous system followed by a slow and long-lasting elimination process compared to prior results where physical particle size reduction methods were applied. With these results, a promising solution and nanocarrier is proposed for the successful transport of non-steroidal anti-inflammatory drugs with acidic character to the brain.

Aim/IntroductionThe study aimed to determine the effectiveness of early antidiabetic therapy in reversing metabolic changes caused by high-fat and high-sucrose diet (HFHSD) in both sexes.MethodsElderly Sprague–Dawley rats, 45 weeks old, were randomized into four groups: a control group fed on the standard diet (STD), one group fed the HFHSD, and two groups fed the HFHSD along with long-term treatment of either metformin (HFHSD+M) or liraglutide (HFHSD+L). Antidiabetic treatment started 5 weeks after the introduction of the diet and lasted 13 weeks until the animals were 64 weeks old.ResultsUnexpectedly, HFHSD-fed animals did not gain weight but underwent significant metabolic changes. Both antidiabetic treatments produced sex-specific effects, but neither prevented the onset of prediabetes nor diabetes.ConclusionLiraglutide vested benefits to liver and skeletal muscle tissue in males but induced signs of insulin resistance in females.

Background and purpose - Ciprofloxacin (CIP) is a broad-spectrum antibiotic widely used in clinical practice to treat musculoskeletal infections. Fluoroquinolone-induced neurotoxic adverse events have been reported in a few case reports, all the preclinical studies on its neuropsychiatric side effects involved only healthy animals. This study firstly investigated the behavioral effects of CIP in an osteoarthritis rat model with joint destruction and pain, which can simulate inflammation-associated musculoskeletal pain. Furthermore, effects of CIP on regional brain-derived neurotrophic factor (BDNF) expression were examined given its major contributions to the neuromodulation and plasticity underlying behavior and cognition. Methods - Fourteen days after induction of chronic osteoarthritis, animals were administered vehicle, 33 mg/kg or 100 mg/kg CIP for five days intraperitoneally. Motor activity, behavioral motivation, and psychomotor learning were examined in a reward-based behavioral test (Ambitus) on Day 4 and sensorimotor gating by the prepulse inhibition test on Day 5. Thereafter, the prolonged BDNF mRNA and protein expression levels were measured in the hippocampus and the prefrontal cortex. Results - CIP dose-dependently reduced both locomotion and reward-motivated exploratory activity, accompanied with impaired learning ability. In contrast, there were no significant differences in startle reflex and sensory gating among treatment groups; however, CIP treatment reduced motor activity of the animals in this test, too. These alterations were associated with reduced BDNF mRNA and protein expression levels in the hippocampus but not the prefrontal cortex. Conclusion - This study revealed the detrimental effects of CIP treatment on locomotor activity and motivation/learning ability during osteoarthritic condition, which might be due to, at least partially, deficient hippocampal BDNF expression and ensuing impairments in neural and synaptic plasticity.