Dexmedetomidine, an alpha-2 adrenoceptors agonist, provides a neuroprotective effect for dopaminergic neurons in the substantia nigra and attenuates glucose imbalance in the 6-hydroxydopamine animal model of Parkinson's disease.

INTRODUCTION: Studies have shown that dexmedetomidine (DEX, an a2-adrenoceptors agonist) provides a neuroprotective effect and influences blood glucose levels. Here, we evaluated the effect of prolonged treatment with low doses of DEX on the survival rate of dopaminergic (DAergic) neurons in the substantia nigra and also serum glucose levels in 6-hydroxydopamine (6-OHDA) - induced Parkinson's disease (PD) in the rat. MATERIAL AND METHODS: The neurotoxin of 6-OHDA was injected into the medial forebrain bundle by stereotaxic surgery. DEX (25 and 50 µg/kg, i.p) and yohimbine, an a2-adrenoceptor antagonist (1 mg/kg, i.p) were administered before the surgery to the 13 weeks afterward. Apomorphine-induced rotational tests and blood sampling were carried out before the surgery and multiple weeks after that. Thirteen weeks after the surgery, the rats' brain was transcardially perfused to assess the survival rate of DAergic neurons using the tyrosine hydroxylase (TH) immunohistochemistry. RESULTS: DEX remarkably attenuated the severity of rotational behavior and reversed the progress of the PD. It also increased the number of TH-labeled neurons by up to 60%. The serum glucose levels in 6-OHDA-received rats did not change in the third and seventh weeks after the surgery but decreased significantly in the thirteenth week. Treatment with DEX prevented this decrement in glucose levels. On the other hand, Treatment with yohimbine did not affect PD symptoms and glucose levels. CONCLUSION: Our data indicate that DEX through neuroprotective activity attenuates the severity of 6-OHDA-induced PD in rats. DEX might also prevent hypoglycemia during the progress of the PD.

Evaluation of mechanisms of colistin resistance in Klebsiella pneumoniae strains isolated from patients with urinary tract infection in ICU.

Background and Objectives: One of the major causes of urinary tract infections is Klebsiella pneumoniae. Currently, few studies investigated the mechanisms of resistance to colistin in Iran. The current study aimed to determine the prevalence of plasmid and chromosome-mediated resistance to colistin in K. pneumoniae isolates. Materials and Methods: 177 urine samples were collected from patients with urinary tract infections hospitalized in the intensive care unit (ICU) of hospitals in the city of Qazvin. K. pneumoniae isolates were identified by standard biochemical methods, resistance to colistin among K. pneumoniae isolates were tested by disk diffusion and microbroth dilution methods. The chromosomal mutation and presence of the mcr genes in colistin-resistant K. pneumoniae were evaluated by PCR. Results: Out of 177 samples, 65 K. pneumoniae were obtained from patients in the ICU. Six colistin-resistant isolates were isolated with MIC values ≥4 µg/mL, none of them was positive for mcr1-5. In 4 isolates, missense mutation in mgrB gene resulted in amino acid substitutions and in one isolate of mgrB gene was found intact mgrB gene. Conclusion: The results suggest that mgrB mutation was the main mutation among colistin-resistant isolates and plasmid-borne colistin resistance was not expanded among strains.

Circulating salivary and serum miRNA-182, 320a, 375 and 503 expression levels in type 2 diabetes.

Aim: Early-stage diagnosis of diabetes through non-invasive and diagnostic biofluid-like saliva has become a very popular approach to facilitate future preventive interventions and improve patient care. Meanwhile, the alteration of small non-coding RNA in human fluids has been suggested as a probable precedent for the early stages of diabetes. Methods: In the present study, we checked the expression of miR-320a, 182-5p, 503, and 375 by using quantitative PCR in both stimulated and unstimulated saliva and blood samples of 40 adult patients with type-2 diabetes compared to 40 healthy individuals. In addition, we have sought to understand the possibility that miRNAs could provide new information about the status of type 2 diabetes in salivary samples beyond what can now be identified from blood samples and link their expression to the presence of clinically relevant risk factors. For this purpose, we have used a set of multivariate models. Results: The results showed that three miRNAs were more highly expressed in patients with type 2 diabetes, while miR-320-a was down-regulated in those patients compared to healthy subjects. Furthermore, the data showed that miR-320a was the most reliable predictor for distinguishing diabetic patients from healthy subjects, with AUCs of 0.997, 0.97, and 0.99 (97.4% sensitivity and 100% specificity, p = 0.001) for serum, unstimulated, and stimulated saliva samples, respectively. Conclusions: Interestingly, the results of this study indicated that the amount of four miRNAs expressed in stimulated saliva was the same as in serum samples, which could conclude that specific miR-320a and 503 in stimulated saliva may introduce credible, non-invasive, and diagnostic biomarkers that can be used to monitor diabetic patients' status, while there is a need to design more research studies to confirm these findings.

Circulating miR-135 May Serve as a Novel Co-biomarker of HbA1c in Type 2 Diabetes.

Hemoglobin A1c (HbA1c) is a reliable marker of insulin resistance in normal glucose tolerance patients; however, several physiological, environmental, and genetic factors may affect HbA1c and cause false results. Therefore, it is essential to use new biomarkers due to increasing diabetes predictive value. Recently, it has been indicated that microRNAs (miRNAs) are involved in the pathophysiology of diabetes, particularly, in insulin resistance pathways. Therefore, miRNAs have the potential to be introduced as new glycemic control biomarkers. The aim of this study was to investigate the association between plasma level of miRNA-135a and HbA1c in patients with prediabetes and type 2 diabetes. In this case-control study, 120 samples were enrolled (healthy individuals, people with type 2 diabetes, and prediabetes) and HbA1c and miR-135a expression level in their plasma samples were evaluated. Multinomial logistic regression and ROC curve analysis were conducted to assess the diagnostic accuracy of plasma miR-135a in T2D , prediabetes, and healthy control groups. Data analysis indicated that miR-135a was significantly elevated in both diabetes/prediabetes samples. Then, subjects were reclassified based on the calculated cutoff value of miRNA. Logistic Regression analysis showed that an increased level of miRNA positively correlated with HbA1c level in prediabetes (Adjusted OR = 1.14, p value = 0.033) and diabetic status (Adjusted OR = 1.27, p value = 0.024 ). miR-135 may provide an assistant marker for HbA1c to detect type 2 diabetes.

Relationship between metabolic syndrome and its components with bone densitometry in postmenopausal women.

BACKGROUND: Prevention of osteoporosis and bone fracture and the relationship between metabolic syndrome and bone density are controversial issues. THE AIM OF THIS STUDY: The aim of this study was to evaluate the association between metabolic syndrome and its components with bone mineral density in post menopausal women referred for bone mineral density (BMD) test. METHODS: A total of 143 postmenopausal women with at least one year of menopause experience participated in this cross-sectional study. Demographic and anthropometric characteristics for all participants were collected. Also, biochemical parameters including fasting blood sugar, Cholesterol (HDL and LDL), triglyceride were measured. Association between the components of metabolic syndrome and bone densitometry were analyzed by statistical methods. RESULTS: In this study, 72% of participants did not have metabolic syndrome. Among them, 43.4% and 28.7% had osteoporosis and normal density, respectively. Of remaining participants with metabolic syndrome, 12.6% and 15.4% had osteoporosis and normal density, respectively. Among the metabolic syndrome components, waist circumference, HDL cholesterol, and waist to hip ratio were significantly associated with bone mass (P<0.05). Osteoporotic women had lower waist circumference and waist to hip ratio and higher HDL than women without osteoporosis. On the other hand, women with metabolic syndrome did not have significant differences than women without metabolic syndrome in terms of lumbar and femoral neck density (P>0.05). CONCLUSION: Results from this study showed that metabolic syndrome and its components did not induce bone mass loss. The discrepancies of the studies in this area call for more large scale studies in population so as to prevent women problems in this area.