Minocycline through attenuation of oxidative stress and inflammatory response reduces the neuropathic pain in a rat model of chronic constriction injury

Objectives: Several lines of evidence showed that minocycline possesses antioxidant and anti-inflammatory properties. This study aimed to demonstrate the effects of minocycline in rats subjected to chronic constriction injury (CCI). Materials and Methods: In this study four groups (n = 6-8) of rats were used as follows: Sham, CCI, CCI + minocycline (MIN) 10 mg/Kg (IP) and CCI + MIN 30 mg/Kg (IP). On days 3, 7, 14, and 21 post-surgery hot-plate, acetone, and von Frey tests were carried out. Finally, Motor Nerve Conduction Velocity Evaluation (MNCV) assessment was performed and spinal cords were harvested in order to measure tissue concentrations of TNF_α, IL-1β, Glutathione peroxidase (GPx), Superoxide dismutase (SOD) and Malondialdehyde (MDA). Extent of perineural inflammation and damage around the sciatic nerve was histopathologically evaluated. Results: Our results demonstrated that CCI significantly caused hyperalgesia and allodynia twenty-one days after CCI. MIN attenuated heat hyperalgesia, cold and mechanical allodynia and MNCV in animals. MIN also decreased the levels of TNF_α and IL-1β. Antioxidative enzymes (SOD, MDA, and GPx) were restored following MIN treatment. Our findings showed that MIN decreased perineural inflammation around the sciatic nerve. According to the results, the neuropathic pain reduced in the CCI hyperalgesia model using 30 mg/kg of minocycline. Conclusion: It is suggested that antinociceptive effects of minocycline might be mediated through the inhibition of inflammatory response and attenuation of oxidative stress

The antinociceptive effects of rosuvastatin in chronic constriction injury model of male rats

Introduction: According to studies, statins possess analgesics and anti-inflammatory properties. In the present study, we examined the antinociceptive, anti-inflammatory and antioxidative effects of rosuvastatin in an experimental model of Chronic Constriction Injury (CCI). Methods: Our study was conducted on four groups; sham, CCI (the control group), CCI+rosuvastatin (i.p. 5 mg/kg), and CCI+rosuvastatin (i.p. 10 mg/kg). We performed heat hyperalgesia, cold and mechanical allodynia tests on the 3rd, 7th, 14th, and 21st after inducing CCI. Blood samples were collected to measure the serum levels of Tumor Necrosis Factor (TNF)-α, and Interleukin (IL)-6. Rats' spinal cords were also examined to measure tissue concentration of Malondialdehyde (MDA), Superoxide Dismutase (SOD), and Glutathione Peroxidase (GPx) enzymes. Results: Our findings showed that CCI resulted in significant increase in heat hyperalgesia, cold and mechanical allodynia on the 7th, 14th and 21st day. Rosuvastatin use attenuated the CCI-induced hyperalgesia and allodynia. Rosuvastatin use also resulted in reduction of TNF-α, IL-6, and MDA levels. However, rosuvastatin therapy increased the concentration of SOD and GPx in the CCI+Ros (5 mg/kg) and the CCI+Ros (10 mg/kg) groups compared to the CCI group. Conclusion: Rosuvastatin attenuated the CCI-induced neuropathic pain and inflammation. Thus, antinociceptive effects of rosuvastatin might be channeled through inhibition of inflammatory biomarkers and antioxidant properties

Mini Nutritional Assessment and its Correlation With Elderly Nursing Home Residents in Khorramabad, Iran

Objectives: Elderly nursing homes residents are at an increased risk of malnutrition due to a variety of factors. We aimed at investigating the prevalence of malnutrition and its correlation with elderly subjects using Mini Nutritional Assessment (MNA) questionnaire. Methods: This cross-sectional study was conducted on elderly individuals (N=56; female=28) dwelling in the Sedigh Nursing Home in Khorramabad, Iran, in 2015. Nutritional status was assessed using MNA, which consisted of anthropometric measurements, global assessment, dietary questionnaire and subjective assessment. Results: The participants mean age was 74.86 (SD=&plusmn;11.82) years. The mean MNA-score of the subjects was 19.46 (SD=&plusmn;3.23). The prevalence of malnutrition and at risk of malnutrition were 20% and 70%, respectively. No significant difference (P>0.05) was observed between male and female, age subgroups, marital status, education levels and different cut-off points of the Body Mass Index (BMI), Mid-Arm Circumferences (MACs) and Calf Circumferences (CCs) regarding the nutritional status of subjects. Malnutrition and risk of malnutrition were observed significantly and more frequently in elderly who had weight loss greater than 3 kg, took more than three prescription drugs per day and had low/moderate protein intake (P<0.05). The MNA-score was independently associated with age, weight, BMI, MACs, CCs and food intake during last 3 months (P<0.05). Discussion: According to high prevalence of malnutrition and risk of malnutrition among the subjects, proper nutritional interventions are required. Longitudinal studies on elderly and primary prevention by lifestyle interventions according to the culture and habits of the region are recommended

Neuroprotective and Anti-inflammatory Role of Atorvastatin and Its Interaction with Nitric Oxide (NO) in Chronic Constriction Injury-induced Neuropathic Pain

Prevention and treatment of neuropathic pain (NP) is one of the most difficult problems in clinical practice since the underlying mechanism of NP is unclear. In previous studies, the increased production of nitric oxide (NO) has been closely linked to the induced NP. In this study, we assessed the effect of atorvastatin through NO mechanism, on inflammation, thermal hyperalgesia, thermal allodynia, and mechanical allodynia as well as sciatic nerve histological score in rat with chronic constriction injury (CCI) model. Finally, we specified the role of cytokines such as TNF-alpha and IL-6 in the spinal cord. Treatment with atorvastatin and L-NAME (NO inhibitor) attenuated the thermal hyperalgesia, thermal allodynia and mechanical allodynia induced by CCI. The antinociceptive consequence was better elevated with a combination of atorvastatin and L-NAME in comparison with the other groups. In addition, the treatment with these drugs also attenuated the CCI-induced TNF-alpha and IL-6 level in the spinal cord. Furthermore, the histological analysis showed a low level of inflammation in the sciatic nerve in the CCI rats co treated with atorvastatin and L-NAME. Findings of our study in NP-induced CCI in the rat model demonstrate that inhibition of NO displays antinociceptive and anti-neuroinflammatory effects of atorvastatin in peripheral and central nervous system. In addition, we found that inhibition of the NO by atorvastatin could be one of the most important anti-inflammatory pathways of atorvastatin effect