Search

Objective Neurorehabilitation that involves learning new motor skills is one of the promising clinical methods for motor recovery in people with multiple sclerosis (PwMS); therefore, factors that influence the acquisition of motor skills in PwMS need to be investigated. Sleep disturbances are common in PwMS; however, no study has investigated the effect of sleep and sleep-related biomarkers on skill acquisition in PwMS. This study aimed to examine the effect of sleep and sleep-related biomarkers on motor acquisition in PwMS. Methods Forty participants with MS and 40 controls were recruited in this study. To assess motor acquisition, each participant was asked to perform a novel game through a virtual reality (VR) system 5 times (blocks). The main outcome measures for each block were the required time to complete the VR game and the recorded errors. The difference in scores between Block 5 and Block 1 for both outcomes were considered to represent motor skill acquisition. Sleep was assessed by self-report using the Pittsburgh Sleep Quality Index (PSQI) and objectively using sleep monitor technology. Serotonin level was assessed using means of enzyme-linked immunosorbent assay using plasma samples. Results There were significant positive correlations in both groups between motor skill acquisition and PSQI score. In PwMS, significant negative correlation between motor skill acquisition and sleep efficiency and significant positive correlation between motor skill acquisition and sleep latency were also observed. Interestingly, a significant negative correlation was observed between motor skill acquisition and the plasma serotonin level in both groups. Most of these correlations remained significant after controlling for disease severity, fatigue, baseline performance, and cognitive status. Conclusion Sleep quality may influence motor skill acquisition in PwMS. Circulatory serotonin level might explain this relationship. Impact Physical therapists are encouraged to be aware of sleep quality and sleep assessment. Sleep management strategies should be considered when treating PwMS. [ABSTRACT FROM AUTHOR]

Abstract Background In recent years there has been a growing appreciation of the issues of career preference in medicine as it may affect student learning and academic performance. However, no such studies have been undertaken in medical schools in Jordan. Therefore, we carried out this study to investigate the career preferences of medical students at Jordan University of Science and Technology and determine factors that might influence their career decisions. Methods A cross-sectional questionnaire-based survey was carried out among second, fourth and sixth year medical students at the Jordan University of Science and Technology, Irbid, Jordan during the academic year 2006/2007. A total of 440 students answered the questionnaire which covered demographic characteristics, specialty preferences, and the factors that influenced these career preferences. Possible influences were selected on the basis of a literature review and discussions with groups of medical students and physicians. Students were asked to consider 14 specialty options and select the most preferred career preference. Results The most preferred specialty expressed by male students was surgery, followed by internal medicine and orthopaedics, while the specialty most preferred by female students was obstetrics and gynaecology, followed by pediatrics and surgery. Students showed little interest in orthopedics, ophthalmology, and dermatology. While 3.1% of females expressed interest in anesthesiology, no male students did. Other specialties were less attractive to most students. Intellectual content of the specialty and the individual's competencies were the most influential on their preference of specialty. Other influential factors were the "reputation of the specialty", "anticipated income", and "focus on urgent care". Conclusion Surgery, internal medicine, pediatrics, and obstetrics and gynaecology were the most preferred specialty preferences of medical students at Jordan University of Science and Technology.

Encephalocraniocutaneous lipomatosis "ECCL" is a rare, sporadic neurocutaneous disorder that results from a lethal autosomal mutation surviving by somatic mosaicism. It is characterized by unilateral involvement of skin, eyes and central nervous system in addition to a propensity for mesenchymal tumors. A 30-year-old male with previously controlled epilepsy presented with recurrent seizures. Brain imaging revealed a left parietal parasagittal enhancing tumor, in addition to left sided gyriform calcifications, and bilateral cerebral atrophy and ventricular dilatation more prominent on the left side. He also presented multiple left sided sebaceous nevi and abundant subcutaneous lipomas in addition to left mandibular condylar cysts. The brain tumor was excised, and cytopathology revealed a WHO grade I fibrous meningioma. After a thorough evaluation and exclusion of alternative diagnoses, the patient was diagnosed with definite encephalocraniocutaneous lipomatosis as per Moog's criteria. Several cases of ECCL recently presented with different intracranial neoplasms. Here we report the first case of ECCL in association with meningioma. [ABSTRACT FROM AUTHOR]

BACKGROUND: Balance deficits are considered a risk factor for falls in MS patients. Therefore, developing innovative approaches such as virtual reality (VR) to improve balance in MS is required. OBJECTIVES: The aims of this study were to develop and evaluate feasibility and acceptability of VR scenarios that target balance in MS using a pilot trial. METHODS: Participants were randomly allocated to either a VR training (i.e. intervention group) (n = 20) or a control group (n = 20). Intervention group received VR training for 6 weeks. Control group received home-based traditional balance exercises without the VR. Participants were assessed at baseline and follow-up on Berg Balance Scale (BBS), Timed Up and Go (TUG), the 10 Meter Walk Test (10-MWT). the 3 Minute Walk Distance (3-MWD), the Modified Fatigue Impact Scale (MFIS) Fall Efficacy Scale- International (FES-I) and the Short Form 36 (SF-36). RESULTS: Six VR scenarios were developed. Sixteen participants in the intervention and 16 in the control group completed the study. Significant differences between the two groups were observed at on BBS, MFIS and several outcomes of the SF-36 survey (P<0.05). Participants reported overall level of satisfaction with the developed VR scenarios. CONCLUSIONS: Findings demonstrated the feasibility and acceptability of a VR-based program in MS individuals. Our findings support the implementation of a larger trial of longer-term VR program. [ABSTRACT FROM AUTHOR]

The epidemiology of multiple sclerosis (MS) is rapidly changing in many parts of the world. In a geographic area that was previously associated with low prevalence, recent studies showing high prevalence and fast rising incidence of MS in the Levant countries led us neurologists of this region to meet in a consensus panel, in order to share our latest findings in terms of MS epidemiology and consent on MS management in the Levant. Twelve neurologists and MS experts representing various countries of the Levant (Lebanon, Syria, Jordan and Iraq) have met in Beirut on the 17th of February 2013, shared their latest epidemiological findings, discussed recent MS aspects in the region, and drafted a consensus on MS management relevant to this geographic area. [ABSTRACT FROM AUTHOR]

• Correlation of motor disability and TNF-α levels is well established in MS patients. • We demonstrate that serum TNF-α levels correlate with the scores of cognitive function scales scores in MS patients in addition to its correlation with motor disability. • Therefore, serum TNF- α Level could be a predictor of cognitive performance in MS Patients. • Our study reinforces the possible role for TNF-α as a therapeutic target in cognitively impaired MS patients. Cognitive dysfunction is an important feature and source of disability for patients with multiple sclerosis (MS). The correlation of cognitive function scales' scores and serum levels of the proinflammatory cytokine tumor necrosis factor-alpha (TNF-α) in MS is not well established. We aim to investigate the correlation of TNF-α serum levels with cognitive function as measured by multiple cognitive scales in patients with MS. Eligible sequential MS patients attending neurology clinics between October 2018 and June 2019 at King Abdulla University Hospital (KAUH) in Jordan were included. Demographic data were collected from all participants. Motor disability was measured using the Expanded Disability Status Score (EDSS), the Functional System Score (FSS), as well as the Patient Determined Disease Steps (PDDS). The Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) and the Montreal Cognitive Assessment (MOCA) were used to evaluate the cognitive status. TNF-α serum levels were measured for each patient. Correlations of TNF-α levels with cognitive function scales' scores and motor disability scores were statistically analyzed. A total of 88 MS patients were included in the study. The mean age (± SD) was 35.78 (± 10.30) years, and 72.7% were females. The majority of patients (82) had relapsing multiple sclerosis (RMS). Serum TNF-α levels were significantly correlated with scores of motor disability scales in the whole patient cohort (EDSS: Pearson correlation coefficient r = 0.230, p=0.031; FSS: r = 0.260, p=0.022; and PDDS: r = 0.261, p=0.014) and in females, but not in males. In the whole cohort, the correlation between TNF-α and EDSS score was also statistically significant (r = 0.216, p=0.047) after adjustment for confounding factors including age, disease duration, and type of MS. Likewise, Serum TNF-α levels were correlated with the scores of cognitive function scales in the whole patient cohort (BICAMS: r = -0.328, p=0.002; and MOCA: r = -0.256, p=0.016). After adjusting for age, gender, education, type of MS, and EDSS score, cognitive performance was still negatively correlated with TNF-α levels (p<0.05). Our findings confirm the presence of a significant correlation between TNF-α levels and different cognitive scales' scores in MS patients. [ABSTRACT FROM AUTHOR]

Background: Multiple sclerosis (MS) is a neurological disease that is caused by an autoimmune response that results in the neuron's demyelination in the central nervous system. The exact etiology of MS is not clear; however, several environmental and genetic factors are believed to participate in its initiation and development, including exposure to viruses. This study aims to investigate the association between the seropositivity and antibody titer of selected herpesviruses and MS in Jordanian MS patients.Method: In this study, 55 MS patients and 40 age- and gender-matching apparently healthy volunteers were recruited from two main hospitals in the north of Jordan. MS patients were grouped into three types of MS based on the clinical presentation of the disease. Blood samples were collected from the participants and the IgG antibodies for human herpesvirus 6 (HHV-6), Epstein-Barr virus (EBV) nuclear antigen (EBNA), EBV viral capsid antigen (VCA) and varicella-zoster virus (VZV) were assayed by ELISA. The prevalence of seropositivity and the antibody level for each of the antibodies were compared between MS patients and controls and between the three types of MS.Results: There was no significant difference in the prevalence of seropositivity and in the levels of antibodies for HHV-6, EBNA and VCA between MS patients and controls and between the three types of MS. In contrast, the number of seropositive patients and the level of IgG antibodies for VZV were significantly higher in MS patients compared to the control.Conclusion: This study showed that patients with MS in the north of Jordan were more likely to be seropositive for VZV than the general population. Based on this finding, we recommend further studies to evaluate the seropositivity to VZV to be carried out in other parts of Jordan and the greater middle east to find out if there is a correlation between MS and previous infection with VZV. [ABSTRACT FROM AUTHOR]

Chronic pain is a persistent and debilitating health problem. Although the use of analgesics such as opioids is useful in mitigating pain, their prolonged use is associated with unwanted effects including abuse liability. This study assesses the antinociceptive effect of combining subtherapeutic doses of two opioids (morphine or tramadol) with the synthetic cannabinoid CP55940 (2-[(1R,2R,5R)-5-hydroxy-2-(3-hydroxypropyl)cyclohexyl]-5-(2-methyloctan -2-yl)phenol). It also evaluates the associated adverse effects of these drugs and combinations. Adult male rats were injected with intraplantar complete Freund's adjuvant (CFA) to produce mechanical allodyia. Antinociceptive effect of morphine, tramadol, the synthetic cannabinoid CP55940, or their combinations was evaluated three to nine days post-CFA injections. Intracranial self-stimulation (ICSS) was utilized to evaluate the abuse liability of these drugs or their combinations. All drugs alone produced a dose-dependent antinociceptive effect. Morphine produced minimal effect on ICSS, but both tramadol and CP55940 produced dose-dependent depression of ICSS. Morphine at a dose of 0.32 mg/kg enhanced the antinociceptive effects of CP55940, in that, CP55940 produced antinociception at a lower dose (0.1 mg/kg) when compared to the vehicle. The aforementioned combinations did not change CP55940-induced depression of ICSS. On the other hand, tramadol failed to enhance the antinociceptive effect of CP55940. Our data suggest that combining CP55940 with morphine, but not tramadol, shows a better antinociceptive profile with no additional risk of abuse liability, which represents a potential pain management approach. [ABSTRACT FROM AUTHOR]

Pain in Parkinson's disease (PD) is a highly prevalent non-motor symptom occurring in this population. The King's PD Pain Scale (KPPS) was developed to assess pain in people with PD. This study aimed to provide a cross-cultural adaptation and translation of the KPPS into the Arabic language (A-KPPS), and to investigate the construct and convergent validity, internal consistency, and reliability of the translated scale. The English KPPS was translated into Arabic and back-translated into English by an independent translation team. The Arabic version was tested in 103 native Arabic speaking PD patients. We assessed construct validity, convergent validity, and test-retest reliability of the A-KPPS using factor analysis method, comparison with other valid and reliable measures, and using intra-class correlations, respectively. The A-KPPS had three main factors "somatic pain", "visceral and burning pain" and "orofacial pain", rather than the original four factors scale. The A-KPPS correlated with measures of disease motor severity, depression, anxiety, quality of life and pain (p < 0.05). Furthermore, the A-KPPS total score had high test-retest reliability (ICC = 0.9). The A-KPPS demonstrated moderate to good validity and reliability. The A-KPPS can facilitate the assessment and treatment of pain in Arabic-speaking people with PD worldwide. Pain is a highly prevalent non-motor symptom of Parkinson's disease (PD) that is often overlooked. The King's PD Pain Scale (KPPS) is specially designed to assess pain localization, intensity, and frequency in people with PD. The Arabic translation of the KPPS is a valid and reliable tool for the assessment of pain in Arabic speaking people with PD. [ABSTRACT FROM AUTHOR]

Recent studies highlighted the role of astrocytes in neuroinflammatory diseases, particularly multiple sclerosis, interacting closely with other CNS components but also with the immune cells. However, due to the difficulty in obtaining human astrocytes, their role in these pathologies is still unclear. In this study we develop an astrocyte in vitro model to evaluate their role in multiple sclerosis after being treated with CSF isolated from both healthy and MS diagnosed patients. Gene expression and ELISA assays reveal that several pro-inflammatory markers IL-1β, TNF-α and IL-6, were significantly downregulated in astrocytes treated with MS-CSF. In contrast, neurotrophic survival, and growth factors, and GFAP, BDNF, GDNF and VEGF, were markedly elevated upon the same treatment. In summary, this study supports the notion of the astrocyte involvement in MS. The results reveal the neuroprotective role of astrocyte in MS pathogenicity by suppressing excessive inflammation and increasing the expression of tropic factors. [ABSTRACT FROM AUTHOR]

Endoscopic resection can be used for removing colloid cysts as a substitute for open craniotomy. Cerebral vasospasm, a possible complication of the craniotomy procedure, has not been reported as a complication of endoscopic removal of colloid cysts. A 58-year-old man developed the worst headache of his life. The CT and MRI showed a 1.3 cm midline third ventricular cyst at the level of the foramen of Monro, consistent with a colloid cyst. The patient elected to undergo an endoscopic resection of the colloid cyst. The image-guided frameless stereotactic endoscopic colloid cyst resection proceeded without events. Postoperative MRI showed a gross total resection. The patient continued to improve until post-operative day #9 when he experienced an episode of slurred speech and several episodes of legs buckling. An MRI did not show a stroke. A CT angiogram showed diffuse vasospasm, including the basilar artery and bilateral middle cerebral arteries, when compared to the patient's preoperative MRA. The patient's antihypertensive medications were stopped. The patient was started on Nimodipine, 60 mg every 4 hours, and triple H therapy (Hypertension, Hypervolemia, and Hemodilution) was applied. His blood pressure rose and his neurologic exam improved over several days. The patient returned to his baseline in 14 days without any neurological deficits. To our knowledge, this is the first case report of a patient undergoing endoscopic colloid cyst resection that was complicated by diffuse cerebral vasospasm. We report the first case of acute, transient cerebral vasospasm following endoscopic resection of a colloid cyst. [ABSTRACT FROM AUTHOR]

Background: Bipolar disorder (BD) is a psychiatric disorder characterized by episodes of depression and mania, associated with impaired emotion processing. Several functional MRI (fMRI) studies have been used to investigate the structural and functional alteration in BD. Here, we aim to investigate the current fMRI findings of brain activation during emotion-regulation tasks between BD patients and healthy controls (HC).Methods: A systematic search through PubMed database for fMRI studies on bipolar patients and HC yielded 685 studies. We performed an activation likelihood estimation (ALE) on 21 studies for emotion regulation in BD patients and HC. Furthermore, we performed subgroup analyses for task performances in response time and accuracy between bipolar patients and HC.Results: The total sample included 21 fMRI studies, comprising 543 BD patients, compared to 565 HC. ALE maps for emotion-related tasks showed hyperactivation in BD patients in the caudate, amygdala, precentral gyrus, middle frontal gyri, and sub-gyrus. Whereas hypoactivation was seen in the inferior frontal gyrus and anterior cingulate gyrus.Limitations: We could not apply a correction for p-value thresholds, as it needs large number of foci. Second, functional abnormalities were investigated for adult BD patients only, as BD patients have functional differences correlated with age.Conclusions: Our results showed that limbic and cortical regions can represent a potential biomarker for the diagnosis and management of BD, by showing clustered brain regions of abnormal patterns of increased activation between BD patients and HC. [ABSTRACT FROM AUTHOR]

Chronic pain has a debilitating consequences on health and lifestyle. The currently available analgesics are often ineffective and accompanied by undesirable adverse effects. Although adenosine receptors (AR) activation can affect nociceptive, inflammatory, and neuropathic pain states, the specific regulatory functions of its subtypes (A1, A2A, A2B and A3 ARs) are not fully understood. The aim of this study was to investigate the role of different AR ligands on inflammatory pain. The von Frey filament test was used to assess the anti-nociceptive effects of adenosine ligands on Complete Freund's Adjuvant (CFA)-induced mechanical allodynia in (180–220 g) adult male Sprague Dawley rats (expressed as paw withdrawal threshold, PWT). Neither the A2AAR selective agonist CGS 21680 hydrochloride (0.1, 0.32 and 1 mg/kg) nor the A2BAR selective agonist BAY 60-6583 (0.1, 0.32 and 1 mg/kg) produced any significant reversal of the PWT. However, the A1AR selective agonist (±)-5′-Chloro-5′-deoxy-ENBA, the A3AR selective agonist 2-Cl-IB-MECA, the A2AAR selective antagonist ZM 241385 and the A2BAR selective antagonist PSB 603 produced a significant reversal of the PWT at the highest dose of 1 mg/kg. Co-administration of the selective antagonists of A1AR and A3AR PSB36 (1 mg/ml) and MRS-3777 (1 mg/ml); respectively, significantly reversed the anti-nociceptive effects of their corresponding agonists. Furthermore, calcium imaging studies reveled that the effective AR ligands in the behavioral assay also significantly inhibit capsaicin-evoked calcium responses in cultured rat dorsal root ganglia (DRG) neurons. In conclusion, modulating the activity of the transient receptor potential vanilloid 1 (TRPV1) receptor by ARs ligands could explain their anti-nociceptive effects observed in vivo. Therefore, the cross talk between ARs and TRPV1 receptor may represent a promising targets for the treatment of inflammatory pain conditions. [ABSTRACT FROM AUTHOR]

Inflammatory reactions in the body have been shown to contribute to migraine development. Therefore, genes involved in the inflammatory pathways might play a role in the susceptibility and development of migraine. In this study, polymorphisms in tumor necrosis factor alpha (TNFα) and lymphotoxin alpha (LTA) genes were tested for association with migraine. A total of 398 participants (198 migraine patients and 200 controls) were recruited in the study. Serum TNF level was measured using a sandwich ELISA kit. Lymphocytes' and monocytes' counts were obtained from a differential complete blood count profile. Participants' DNA was extracted and genotyped for rs1800629 and rs1799724 in TNFα, and rs909253 in LTA. Controls had a significantly higher mean lymphocyte count (P = 0.018), while the mean monocyte count and serum TNFα levels did not differ between the two groups (P > 0.05). With respect to gene polymorphisms, the rs1800629 and rs1799724 variants showed significant association with migraine in all subjects, and in males and females when analyzed separately (P < 0.001). The rs909253 did not show any statistical difference in frequencies among the two groups (P > 0.05). Having the A allele in rs1800629 was associated with a higher risk of migraine in both male (OR, 95%; CI, G/A = 3.79 [1.87-7.69]; A/A = 14.22 [1.67-121.14]; P < 0.01) and female (OR, 95%; G/A = 2.54 [1.47-4.38]; A/A = 2.52 [1.12-5.69]; P < 0.001) subjects. In conclusion, rs1800629 and rs1799724 in TNFα showed significant association with migraine among the Jordanian population. [ABSTRACT FROM AUTHOR]

Background: The spectrum of neurological involvement in COVID-19 is not thoroughly understood. To the best of our knowledge, no systematic review with meta-analysis and a sub-group comparison between severe and non-severe cases has been published. The aim of this study is to assess the frequency of neurological manifestations and complications, identify the neurodiagnostic findings, and compare these aspects between severe and non-severe COVID-19 cases.Methods: A systematic search of PubMed, Scopus, EBSCO, Web of Science, and Google Scholar databases was conducted for studies published between the 1st of January 2020 and 22nd of April 2020. In addition, we scanned the bibliography of included studies to identify other potentially eligible studies. The criteria for eligibility included studies published in English language (or translated to English), those involving patients with COVID-19 of all age groups, and reporting neurological findings. Data were extracted from eligible studies. Meta-analyses were conducted using comprehensive meta-analysis software. Random-effects model was used to calculate the pooled percentages and means with their 95% confidence intervals (CIs). Sensitivity analysis was performed to assess the effect of individual studies on the summary estimate. A subgroup analysis was conducted according to severity. The main outcomes of the study were to identify the frequency and nature of neurological manifestations and complications, and the neuro-diagnostic findings in COVID-19 patients.Results: 44 articles were included with a pooled sample size of 13,480 patients. The mean age was 50.3 years and 53% were males. The most common neurological manifestations were: Myalgia (22.2, 95% CI, 17.2 to 28.1%), taste impairment (19.6, 95% CI, 3.8 to 60.1%), smell impairment (18.3, 95% CI, 15.4 to 76.2%), headache (12.1, 95% CI, 9.1 to 15.8%), dizziness (11.3, 95% CI, 8.5 to 15.0%), and encephalopathy (9.4, 95% CI, 2.8 to 26.6%). Nearly 2.5% (95% CI, 1 to 6.1%) of patients had acute cerebrovascular diseases (CVD). Myalgia, elevated CK and LDH, and acute CVD were significantly more common in severe cases. Moreover, 20 case reports were assessed qualitatively, and their data presented separately.Conclusions: Neurological involvement is common in COVID-19 patients. Early recognition and vigilance of such involvement might impact their overall outcomes. [ABSTRACT FROM AUTHOR]

• This is the first study that addresses the value of automatic SPECT injectors (ASIs) in adult epilepsy monitoring unit (EMU). • ASIs were superior in terms of shorter injection latency (IL) and a lower ratio of IL/ total seizure duration, leading to more localizing iSPECTs. • ASIs were associated with no isotope spills and thus provided more safety for the EMU patients and staff. • ASIs optimize the diagnostic yield of iSPECT and improve the presurgical evaluation of patients with drug-resistant epilepsy. Ictal Single Photon Emission Computed Tomography (iSPECT) is one of the established tools utilized in the presurgical evaluation of patients with drug-resistant epilepsy (DRE). Timely isotope injection for an iSPECT is critical for optimal yield but poses logistical challenges when done manually. We aim to evaluate the added value of automatic iSPECT injectors (ASIs) in overcoming such challenges. We retrospectively reviewed all cases admitted to the University of Pittsburgh Medical Center (UPMC) Epilepsy Monitoring Unit from Jan 1, 2010, through Dec 31, 2016, who underwent an iSPECT. We compared the manually injected iSPECTs with those performed with ASIs. A total of 123 iSPECTs were reviewed. The manually injected iSPECT group consisted of 35 patients (median age, 35 years; and 19 males). The automatically injected iSPECT group consisted of 88 patients (median age, 36 years; and 46 males). The two groups were comparable in age, gender, epilepsy treatment, focal features on neuropsychological testing (NPT), EEG, and MRI, and temporal origin of seizures (p > 0.05). Compared to manually injected iSPECTs, automatically injected ISPECTs' median injection latency (IL) was shorter (18.5 vs. 60 s, p < 0.001); the ratio of IL/total duration of seizure was lower (0.395 vs. 0.677, p < 0.001); postictal injections were less frequent (4 (4.5 %) vs. 7 (20 %), p = 0.007); the number of isotope spills was less (zero vs. 3, p = 0.022); and successfully localizing iSPECTs were more prevalent (81.8 % vs. 62.9 %, p = 0.025), even after adjusting for focal features on NPT, EEG, and MRI, the temporal origin of seizures, and seizure duration (OR of 5.539, 95 %CI = 1.653–18.563, p = 0.006). Utilization of ASIs leads to a significant shortening of iSPECT IL with less postictal injections, provides a safer injection option for the EMU staff, and leads to a significant improvement in the number of successfully localizing iSPECTs. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is characterized by cartilage degeneration, subchondral sclerosis, and pain. Cannabinoids have well-established anti-nociceptive properties in animal models of chronic pain. The aim of this study is to evaluate the anti-nociceptive effects of synthetic cannabinoids (WIN-55,212 and HU210) and the cannabinoid-like compound palmitoylethanolamide (PEA) in rat models of OA and to assess the role of cannabinoid receptor 1 (CB1) and the peroxisome proliferator-activated receptor α (PPARα) in mediating these effects. Intra-articular injection of monosodium iodoacetate (MIA) in the knee joint was used as a model of osteoarthritis. The von Frey filament test and weight-bearing difference were used to assess the anti-nociceptive effects of WIN-55,212, HU210, and PEA on MIA-induced OA in rats. Open-field locomotor activity system was used confirm the analgesic effects of those compounds. HU210, WIN55, 212, and PEA in a dose-dependent manner restored the paw withdrawal threshold (PWT) and the weight-bearing difference induced by MIA injection. SR141716A (a CB1 antagonist) significantly reversed the anti-nociceptive effects of all the administered drugs in terms of PWT. However, in terms of weight-bearing difference, SR141716A significantly reduced the anti-nociceptive effect of HU210 but not PEA or WIN55, 212. GW6471 (a PPARα antagonist) significantly reversed the anti-nociceptive effects of PEA but not those of HU210 or WIN55, 212. HU210, WIN55, 212 and PEA significantly restored the MIA-induced reduction in locomotor activity. In conclusions, both CB1 and PPARα receptors are involved in mediating pain in osteoarthritis. Therefore, targeting these receptors may be of great clinical value. [ABSTRACT FROM AUTHOR]