Long Term Sodium Nitrate Administration Positively Impacts Metabolic and Obesity Indices in Ovariectomized Rats.

BACKGROUND: In postmenopausal women, nitric oxide (NO) deficiency is associated with obesity and type 2 diabetes (T2D). This study aims at determining the long-term effects of low-dose nitrate administration on metabolic and obesity indices in ovariectomized (OVX) rats. METHODS: OVX rat model was induced using the two dorsolateral skin incision method. Two months after ovariectomy, rats were divided into three groups (n = 10/group): Control, OVX, and OVX+nitrate, and the latter received sodium nitrate at a dose of 100 mg/L in their drinking water for nine months. Fasting serum glucose and lipid profile were measured every month. A glucose tolerance test was performed at months 1, 3, and 9 (the end of the study). Obesity indices were calculated, and histological analyses were performed on the gonadal adipose tissues at month 9. RESULTS: OVX rats had impaired fasting glucose, glucose intolerance, and dyslipidemia with higher obesity indices at month 9. Nitrate improved glucose and lipid metabolism in OVX rats and decreased body weight (6.9%), body mass index (12.5%), Lee index (5.4%), adiposity index (23.9%), abdominal circumference (10.5%), and thoracic circumference (17.1%). Also, nitrate decreased adipocyte area by 49% and increased adipocyte density by 193% in gonadal adipose tissue. CONCLUSION: Long-term low-dose nitrate administration improves glucose and lipid metabolism in OVX rats in association with decreasing OVX-induced adiposity, increasing adipocyte density, and decreasing adipocyte area. These findings provide support for a potential therapeutic role of nitrate in postmenopausal women with some features of metabolic syndrome.

Effect of Nitrate on Gene and Protein Expression of Nitric Oxide Synthase Enzymes in Insulin-Sensitive Tissues of Type 2 Diabetic Male Rats

BACKGROUND AND OBJECTIVE: Decreased nitric oxide (NO) bioavailability contributes to the pathophysiology of type 2 diabetes mellitus (T2DM). This study aims to determine the effects of nitrate (NO3 -) on gene and protein expression of NO synthase (NOS) enzymes in the liver, soleus muscle (SM), and epididymal adipose tissue (eAT) of rats with T2DM. METHODS: Twenty-eight male rats were divided into 4 groups: Control, diabetes, control+NO3 -, and diabetes+NO3 - (n = 7/each group). NO3 - was administered for 6 months, and mRNA and protein levels of NOS enzymes were measured at the end of the study. RESULTS: mRNA and protein levels of inducible NOS (iNOS) were higher in the liver (475% and 73%), SM (271% and 43%), and eAT (543% and 24%) of rats with T2DM. In the case of the endothelial NOS (eNOS), diabetic rats had lower mRNA and protein levels in the liver (26% and 24%) and SM (60% and 62%) and lower mRNA level (30%) in eAT. mRNA and protein levels of neural NOS (nNOS) were lower in SM (69% and 73%) and eAT (25% and 31%) of rats with T2DM. NO3 - administration restored disrupted iNOS and eNOS expressions to their near normal values in all the studied tissues; NO3 - also increased nNOS mRNA and protein levels in SM and eAT but decreased nNOS protein level in the liver. CONCLUSION: Long-term NO3 - administration restored disrupted expression of NOS enzymes in the liver, SM, and eAT of rats with T2DM; these findings partly explain the beneficial metabolic effects of nitrate in T2DM.

Effect of inorganic nitrate on metabolic parameters in patients with type 2 diabetes: A 24-week randomized double-blind placebo-controlled clinical trial.

AIM: In this randomized placebo-controlled clinical trial, effect of oral inorganic nitrate (NO3-) on metabolic parameters was assessed in patients with type 2 diabetes mellitus (T2DM). METHODS: Seventy-four eligible patients with T2DM were randomly assigned to NO3--rich beetroot powder (5 g/d contains ~250 mg NO3-) and placebo groups to complete intervention over a 24-week period. Blood HbA1c, fasting serum glucose, insulin, C-peptide, as well as lipid profile were assessed at baseline and again at weeks 4, 12, and 24; indices of insulin resistance were also calculated. To assess safety of long-term oral NO3-, liver and renal function tests were measured. An intention-to-treat approach was used for data analysis. To compare effect of intervention over time between the groups (time×group), repeated measures generalized estimating equation (GEE) linear regression models were used. RESULTS: Mean age of the participants was 54.0 ± 8.5 (47.9% were male) and mean duration of diabetes was 8.5 ± 6.1 years. A total of 64 patients (n = 35 in beetroot group and n = 29 in placebo group) completed at least two visits and were included in the analyses. No significant difference was observed between the groups for glycemic and lipid parameters over time. Liver and renal function tests, as safety outcome measures, showed no undesirable changes during the study follow-up. CONCLUSION: Supplementation with inorganic NO3- had no effect on metabolic parameters in patients with T2DM.

First survey of hard ticks (Acari: Ixodidae) on cattle, sheep and goats in Boeen Zahra and Takistan counties, Iran.

OBJECTIVE: To carry out the distribution survey of hard ticks of livestock in Boeen Zahra and Takistan counties of Qazvin province from April 2010 to September 2010. METHODS: Nearly about 2 638 sheep, 461 goats and 318 cattle of 38 herds in different geographical areas were searched for tick infestation. RESULTS: The species compositions collected from the livestock of Boeen Zahra and Takistan were Haemaphysalis concinna (0.63%), Haemaphysalis sulcata (12.66%), Hyalomma anatolicum (3.80%), Hyalomma asiaticum (3.16%), Hyalomma detritum (5.70%), Hyalomma dromedarii (28.48%), Hyalomma marginatum (13.29%), Hyalomma schulzei (1.89%), Rhipicephalus bursa (3.16%) and Rhipicephalus sanguineus (3.16%), and for Takistan's livestock were Hyalomma dromedarii (9.86%), Hyalomma marginatum (13.29%), Hyalomma schulzei (1.89%) and Rhipicephalus sanguineus (3.16%), respectively. Hard ticks compositions in different topographic areas were different. Hyalomma species had the most prevalence in the areas. CONCLUSIONS: The veterinary and public health investigation of the above species should be taken.

First survey of hard ticks (Acari:Ixodidae) on cattle, sheep and goats in Boeen Zahra and Takistan counties, Iran

Objective: To carry out the distribution survey of hard ticks of livestock in Boeen Zahra and Takistan counties of Qazvin province from April 2010 to September 2010. Methods:Nearly about 2 638 sheep, 461 goats and 318 cattle of 38 herds in different geographical areas were searched for tick infestation. Results:The species compositions collected from the livestock of Boeen Zahra and Takistan were Haemaphysalis concinna (0.63%), Haemaphysalis sulcata (12.66%), Hyalomma anatolicum (3.80%), Hyalomma asiaticum (3.16%), Hyalomma detritum (5.70%), Hyalomma dromedarii (28.48%), Hyalomma marginatum (13.29%), Hyalomma schulzei (1.89%), Rhipicephalus bursa (3.16%) and Rhipicephalus sanguineus (3.16%), and for Takistan’s livestock were Hyalomma dromedarii (9.86%), Hyalomma marginatum (13.29%), Hyalomma schulzei (1.89%) and Rhipicephalus sanguineus (3.16%), respectively. Hard ticks compositions in different topographic areas were different. Hyalomma species had the most prevalence in the areas. Conclusions:The veterinary and public health investigation of the above species should be taken.