Asprosin, a novel glucogenic adipokine: a potential therapeutic implication in diabetes mellitus.

OBJECTIVES: We aimed to investigate the effects of asprosin on diabetes with a focus on serum glucose, irisin, ghrelin, leptin levels and hepatic levels of triglycerides (TG), cholesterol, low-density lipoprotein (LDL). METHODS: Asprosin (10 µg/kg) was administered intraperitoneally four times at 3-day intervals and then blood and hepatic parameters above mentioned were investigated in control and diabetic mice. RESULTS: The administration of asprosin increased blood glucose level in healthy animals (p = .05) whereas it did not change blood glucose level in diabetic animals. In addition, while asprosin decreased irisin level and increased ghrelin level, it did not change leptin level in diabetic mice. Therewithal, asprosin decreased the increasing levels in hepatic TG, cholesterol, and LDL in diabetic mice. CONCLUSIONS: Our novel findings implicate that asprosin may be a target molecule in preventing the development and complications of diabetes.

Gonadotropin levels reduced in seven days immobilization stress-induced depressive-like behavior in female rats.

OBJECTIVES: Reproduction is one of the physiological functions that are often negatively affected by chronic stress. We aimed to examine effects of two distinct 7-day chronic immobilization stress (IMO) models on gonadotropins levels and depression-like behaviors in female rats. METHODS: Adult Wistar albino female rats were divided into three groups as follows (n=7 for each group): control, IMO-1 (45 min daily for 7-day) and IMO-2 (45 min twice a day for 7-day). Neuropsychiatric behaviors were determined by using forced swimming test (FST) and open field test (OFT). Gonadotropins were analyzed using ELISA tests. RESULTS: In FST, swimming was lower, and immobility was higher in the IMO-1 group and IMO--2 group. Climbing score of the IMO-2 group was higher compared to the control group. In OFT, there was no significant alteration in the mean velocity, total distance, duration of time spent in the central area and duration of latency in the central area between the stress groups and the control group. Final body weight and percentage of body weight change were lower in both stress groups. The follicle-stimulating hormone level was lower only in the IMO-2 group, and the luteinizing hormone concentrations were significantly lower in the IMO-1 group and IMO-2 group. CONCLUSIONS: Our results indicated that depression-like behaviors increased, and gonadotropins decreased in the female rats exposed to 7-day chronic IMO.

Agomelatine potentiates anti-nociceptive effects of morphine in a mice model for diabetic neuropathy: involvement of NMDA receptor subtype NR1 within the raphe nucleus and periaqueductal grey.

OBJECTIVES: Opioid analgesics have been used for a long time in the treatment of acute and chronic pain. However, they have many side effects including tolerance development to a significant extent. Agomelatine, an atypical antidepressant, has been demonstrated to be effective in experimental studies on pain. However, the effect of agomelatine on morphine tolerance development and its mechanism of action are unknown. The antinociceptive effects of agomelatine, morphine and their combination were assessed in a mice model for painful diabetic neuropathy. The roles of glutamate ionotropic receptor N-methyl-D-aspartate (NMDA) type subunit-1 (GluN1) in raphe nucleus and periaqueductal gray (PAG) in the effect of agomelatine on neuropathic pain were also investigated in diabetic mice. METHODS: Agomelatine (10 mg/kg), morphine (10 mg/kg) and agomelatine + morphine were administered intraperitoneally for 15 consecutive days (twice per day), and the analgesic responses were assessed at days 1, 3, 6, 9, 12 and 15 in healthy and diabetic mice. Real time polymerase chain reaction (RT-PCR) was used to determine the changes in GluN1 expression. RESULTS: The tolerance development for morphine was evident, started at 6th day and remained thereafter, but not for agomelatine. GluN1 in raphe nucleus and PAG was upregulated in morphine treated but not in agomelatine-treated groups. DISCUSSION: The combination of agomelatine with morphine alone causes outlasting analgesic effects of repeated treatment, which can be interpreted as attenuated tolerance. Moreover, we also pointed out for the first time the modulatory effects of agomelatine on GluN1 expression in raphe nucleus and PAG after chronic morphine treatment. ABBREVIATIONS: Ca2+: Calcium; D2DR: Dopamine D2 receptor; GAPDH: Glyceraldehyde-3-phosphate dehydrogenase; GluN1: Glutamate ionotropic receptor N-methyl-D-aspartate type subunit-1; 5-HT: 5-hydroxytryptamine; i.p.: intraperitoneal injection; MPE: Maximal possible effect; MT: Melatonin; NMDA: N-methyl-D-aspartate; NMDAR1: NMDA receptors-1; PAG: Periaqueductal grey; PKCγ: Protein kinase C gamma; RT-PCR: Real time polymerase chain reaction; STZ: Streptozotocin.

The relationship between metabolic presbycusis and serum paraoxonase/arylesterase activity.

To determine the presence of a relationship between metabolic presbycusis and serum paraoxonase/arylesterase activity. A total of 30 patients who had been admitted to the Ear, Nose, and Throat (ENT) Clinic of Firat University Medical Faculty and diagnosed as metabolic presbycusis were included in the study. The control group was composed of 30 healthy volunteers. Pure tone audiometry and impedencemeter were performed on all subjects included in the study at the audiometry laboratory of the ENT clinic. The presence of a regular hearing curve, a symmetrical sensorineural hearing loss more than 25 dB with preserved speech discrimination were accepted as criteria for metabolic presbycusis. Blood samples were drawn from the patients prior to the hearing tests. The sera were separated for measurements of total cholesterol, triglyceride, high-density lipoprotein, very low-density lipoprotein, low-density lipoprotein, human serum paraoxonase and arylesterase levels, respectively. No statistically significant difference was found between the patient and the control groups in terms of age and gender. Paraoxonase, arylesterase and paraoxonase/arylesterase, high-density lipoprotein levels were found to decrease in the study group and the difference was found to be statistically significant compared to the control group (P < 0.001). Low-density lipoprotein and total cholesterol levels were found to increase in the patient group and the difference was found to be significant compared to the control group (P < 0.001). This study puts forth that especially the type of nutrition and life style are very important with regard to metabolic presbycusis. Furthermore, the results of this study make us think that there could be a relationship between metabolic presbycusis and cardiovascular diseases. In this case, metabolic presbycusis may be a determining parameter in the early diagnosis of cardiovascular diseases. We consider that this study may be the pioneer for further studies conducted with larger patient numbers.

Protective effects of alpha-lipoic Acid on oleic Acid-induced acute lung injury in rats.

BACKGROUND: Oxidative stress is believed to be an important factor in the pathogenesis of acute lung injury (ALI). AIMS: The aim of this study was to investigate the possible protective role of alpha-lipoic acid (α-LA) on oleic acid (OA)-induced ALI in rats. STUDY DESIGN: Animal experiment. METHODS: A total of thirty-five rats were divided into five groups in the study. Group 1 served as a control group. Rats in Group 2 (α-LA) were administered α-LA intraperitoneally at a dose of 100 mg/kg body weight (BW). Rats in Group 3 (OA) were administered OA intravenously at a dose of 100 mg/kg BW. In Group 4 (pre-OA-α-LA), α-LA was given 15 minutes prior to OA infusion, and in Group 5 (post-OA-α-LA), α-LA was given two hours after OA infusion. Four hours after the OA infusion, rats were decapitated. Blood samples were collected to measure serum levels of malondialdehyde (MDA) and glutathione (GSH), and the levels of activity for superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px). Lung tissue samples were taken for histopathological examination. RESULTS: Exposure to OA resulted in increases in serum MDA levels (p<0.001), as well as histopathological lesions in lung tissue, and decreases in CAT (p<0.05), GSH-Px (p<0.05) activities and GSH (p<0.05) levels. On the other hand, MDA levels were decreased significantly (p<0.001), while CAT (p<0.05), GSH-Px (p<0.01) activities and GSH (p<0.05) levels were increased significantly in the pre-OA-α-LA group compared with the OA group. CONCLUSION: α-LA was found to lessen oxidative stress and to have positive effects on antioxidants in cases of OA-induced ALI. In conclusion, α-LA appears to have protective effects against ALI and potential for the prevention of ALI.