PPARγ activation improved learning and memory and attenuated oxidative stress in the hippocampus and cortex of aged rats.

Oxidative stress has an important role in brain aging and its consequences include cognitive decline and physiological disorders. Peroxisome proliferator-activated receptor-γ (PPARγ) activation has been suggested to decrease oxidative stress. In the current research, the effect of PPARγ activation by pioglitazone(Pio) on learning, memory and oxidative stress was evaluated in aged rats. The rats were divided into five groups. In the Control group, vehicle (saline-diluted dimethyl sulfoxide (DMSO)) and saline were injected instead of Pio and scopolamine (Sco), respectively. In the Sco group, the vehicle was injected instead of Pio and the rats were injected by Sco 30 min before the behavioral tests. In the Sco-Pio 10, Sco-Pio 20, and Sco-Pio 30 groups, 10, 20, and 30 mg/kg Pio was injected and finally, the rats were injected with Sco 30 min before the behavioral tests. Morris water mater maze(MWM) and passive avoidance(PA) tests were carried out, and finally, the hippocampus and cortex were removed for biochemical assessments. The results showed that the highest dose of Pio decreased the traveling time and distance during 5 days of learning and increased the time and distance in the target area on the probe day of MWM. The highest dose of Pio also prolonged the delay time for entering the dark and total time spent in the light while decreasing the total time spent in and the number of entries into the dark in PA test. Pio especially, in the medium and highest doses, decreased MDA while increasing thiol, superoxide dismutase, and catalase in the hippocampus and cortex. It is concluded that PPARγ activation by Pio as an agonist improved learning and memory in aged rats probably by attenuating oxidative stress in the hippocampus and cortex.

Multiparametric MRI for the Diagnosis of Tumor Type in Patients Suspicious of Inner Gland Prostate Cancer.

PURPOSE: The current study aimed to evaluate multiparametric MRI for the diagnosis of type of tumor (benign ormalignant) in patients suspicious of inner gland prostate cancer. MATERIALS AND METHODS: This cross-sectional study was conducted on 44 consecutive patients with a clinicalimpression of prostate cancer who were referred to the MRI department of Payambaran Hospital, Tehran, Iranfor confirmative diagnostic evaluation. Cases suspected of tumor relapse and those who previously underwenttreatment for prostate cancer were excluded. Multiparametric MRI was performed for every patient by using a 1.5Tesla device with an integrated endorectal and pelvic-phased array coil. All patients subsequently underwent MRItransrectalultrasound fusion biopsy. The diagnostic value of each sequence was then investigated individually andin combination with other techniques by comparing the results with histological findings from MRI-TRUS fusionbiopsy. RESULTS: Among the techniques, T2-weighted imaging (T2W) had the highest sensitivity and specificity whiledynamic contrast enhanced (DCE) technique had the least. Diffusion-weighted imaging (DWI) and magnetic resonancespectroscopy (MRS) had a similar sensitivity and specificity and did not significantly differ from T2W.Adding functional techniques to T2W did not improve diagnostic indices compared to T2W alone. Quantitativeevaluation of apparent diffusion coefficient (ADC), DWI, and MRS showed that all techniques were able to differentiatebetween benign and malignant tumors. However, the quantitative combination of these sequences decreaseddiagnostic performance. CONCLUSION: T2W is the best technique for the diagnosis of type of tumor in terms of benignancy or malignancyin patients suspicious of inner gland prostate cancer. Adding functional imaging measurements to T2W does notimprove its diagnostic value.