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1.
Sci Rep ; 13(1): 21839, 2023 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-38071388

RESUMO

Hydrogen sulfide (H2S) has many physiological and pathological roles in the human body. Sodium hydrosulfide (NaHS) is widely used as a pharmacological tool for assessing H2S effects in biological experiments. Although H2S loss from NaHS solution is a matter of minutes, some animal studies use NaHS in solution as an H2S-donating compound in drinking water. This study addresses whether 30 µM NaHS in drinking water prepared in rat/mouse water bottles remains stable for at least 12-24 h, as presumed by some authors. NaHS solutions (30 µM) were prepared in drinking water and immediately transferred to rat/mice water bottles. Samples were obtained from the tip of water bottles and from inside of the bottles at 0, 1, 2, 3, 4, 5, 6, 12, and 24 h for sulfide measurement using the methylene blue method. Furthermore, NaHS (30 µM) was administered to male and female rats for two weeks, and serum sulfide concentrations were measured every other day in the first week and at the end of the second week. NaHS solution was unstable in the samples obtained from the tip of water bottles; it declined by 72% and 75% after 12 and 24 h, respectively. In the samples obtained from the inside of the water bottles, the decline in the NaHS was not significant until 2 h; however, it decreased by 47% and 72% after 12 and 24 h, respectively. NaHS administration did not affect serum sulfide levels in male and female rats. In conclusion, NaHS solution prepared in drinking water can not be used for H2S donation as the solution is unstable. This route of administration exposes animals to variable and lower-than-expected amounts of NaHS.


Assuntos
Água Potável , Sulfeto de Hidrogênio , Humanos , Ratos , Masculino , Feminino , Camundongos , Animais , Sulfeto de Hidrogênio/farmacologia , Sulfetos/farmacologia , Animais de Laboratório
2.
Pharmacol Rep ; 75(4): 979-994, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37258800

RESUMO

BACKGROUND: Menopause is associated with higher risks of chronic kidney disease. We determined the effect of nitrate on ovariectomy-induced kidney dysfunction METHODS: Control, ovariectomized (OVX), control + nitrate, and OVX + nitrate female Wistar rats (n = 10/group); sodium nitrate (100 mg/L) administered in drinking water for 9 months. Glomerular filtration rate (GFR) and albumin excretion rate (AER) were calculated from serum and urine parameters. At month 9, serum and kidney levels of nitric oxide (NO) metabolites (NOx), oxidative stress indices, and mRNA expression of endothelial NO synthase (eNOS) were measured; with histological analyses of the kidney. RESULTS: Compared to controls, OVX rats had lower GFR (31%, p = 0.0079), higher glomerular tuft volume (30%, p = 0.0402), and Bowman's capsule space (39%, p = 0.0224). OVX rats had lower serum NOx (33%, p = 0.0061) and kidney eNOS mRNA expression (34%, p = 0.0368). Nitrate administration to: (i) control rats increased serum NOx (59%, p < 0.0001), with no effect on other parameters; (ii) OVX rats increased serum (85%, p < 0.0001) and kidney (106%, p = 0.0008) NOx values, and restored kidney eNOS expression to normal value. Nitrate administration to OVX rats increased GFR (36%, p = 0.0361) and restored glomerular tuft volume and Bowman's capsule space to normal values. In OVX rats, it also increased serum catalase (CAT) activity, serum and kidney total antioxidant capacity (TAC), and decreased serum malondialdehyde (MDA). CONCLUSIONS: Low-dose long-term nitrate administration protects against ovariectomy-induced kidney dysfunction in rats. This effect is associated with reducing ovariectomy-induced oxidative stress and restoring eNOS-derived NO deficiency in systemic circulation and the kidney.


Assuntos
Antioxidantes , Nitratos , Ratos , Feminino , Animais , Humanos , Ratos Wistar , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Rim , Ovariectomia , RNA Mensageiro
3.
BMC Endocr Disord ; 22(1): 59, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260113

RESUMO

AIM: This study aimed to determine the association of urinary microalbumin concentrations with type 2 diabetes mellitus (T2DM), metabolic syndrome (MetS), and its phenotypes. The optimum cut-off values of urinary microalbumin and microalbumin-to-creatinine ratio (MCR) for predicting the chance of having T2DM and MetS were also defined. METHODS: Adult men and women (n = 1192) participated in the sixth phase (2014-2017) of the Tehran Lipid and Glucose Study (TLGS), with completed data, were included in the analyses. Odds ratios (ORs) (and 95% confidence intervals (CIs)) of T2DM, MetS, and its components across tertile categories of urinary microalbumin concentrations were estimated using multivariable logistic regressions. The optimal cut-off points of urinary microalbumin and MCR were determined using the receiver operator characteristic (ROC) curve analysis. RESULTS: Participants' mean (±SD) age was 44.9 (±14.0) years, and 44.6% of the participants were men. The prevalence of microalbuminuria was 14.4%. Chance of having T2DM was significantly higher in the highest tertile of urinary microalbumin concentration (OR = 2.29, 95% CI = 1.43-3.67) and MCR (OR = 1.82, 95% CI = 1.15-2.89). Subjects with the highest urinary microalbumin concentration were more likely to have MetS (OR = 1.66, 95% CI = 1.17-2.35), hypertension (OR = 1.63, 95% CI = 1.16-2.30) and hyperglycemia (OR = 1.78, 95% CI = 1.24-2.56). No significant association was observed between urinary microalbumin concentrations and other components of MetS. The optimal cut-off points of urinary microalbumin for predicting the chance of having T2DM and MetS were 14.0 and 13.6 mg/L, respectively. CONCLUSIONS: Elevated spot urinary microalbumin, below the values defined as microalbuminuria, was associated with the chance of having T2DM and MetS.


Assuntos
Albuminas/metabolismo , Creatinina/urina , Diabetes Mellitus Tipo 2/urina , Síndrome Metabólica/urina , Adulto , Feminino , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Nutr Metab (Lond) ; 19(1): 19, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35292052

RESUMO

BACKGROUND: We aimed to estimate salt intake among an Iranian population using spot urine-based equations and a dietary-based method. METHODS: Adult men and women (n = 2069) were recruited from the Tehran Lipid and Glucose Study (2014-2017). Urinary sodium (Na), potassium (K), and creatinine (Cr) concentrations were measured in the morning spot urine samples. The 24-h urinary Na excretion and predicted salt intake was estimated using five equations, i.e., Kawasaki, Tanaka, Intersalt, Toft, and Whitton. A validated food frequency questionnaire (FFQ) was used to obtain dietary intake of salt. The agreement of each urinary- and FFQ-based salt estimation with the overall mean of the methods, considered as the gold standard, was assessed using the Bland-Altman method. RESULTS: Mean age of the participants was 45.6 ± 14.8 y, and 45.4% were men. Mean (SD) estimated salt intake, derived from the overall mean of the methods, was 9.0 ± 2.2 g/d (10.2 ± 2.1 and 7.9 ± 1.7 g/d in men and women, respectively). Mean bias of the estimations from the overall mean ranged from - 0.2.42 to 2.75 g/d, with the Tanaka equation having the least bias (mean bias = 0.13 ± 1.10, 95% CI - 2.37, 2.30 g/d). Tanaka estimated a mean salt intake of 8.9 g/d (range 2.1 to 18.7 g/d); accordingly, only 5.1% of participants adhered to the recommendation (< 5 g/d salt intake), whereas 26.8% and 2.4% exceeded the recommendation by 2- and threefold. CONCLUSION: The Tanaka equation could provide a more accurate mean-population estimated salt intake from casual urinary Na concentration in our population. About 95% of the Iranian population exceeded the current recommendations of salt intake.

5.
Arch Med Res ; 53(2): 147-156, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34696904

RESUMO

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.


Assuntos
Diabetes Mellitus Tipo 2 , Nitratos , Adiposidade , Animais , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Nitratos/farmacologia , Nitratos/uso terapêutico , Obesidade/metabolismo , Ratos
6.
Eur J Med Res ; 26(1): 3, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407860

RESUMO

BACKGROUND: Current evidence regarding the prognostic relevance of urinary sodium-to-potassium ratio (Na-to-K ratio), as an indicator of diet quality is limited. This study was conducted to investigate whether urinary Na-to-K ratio could be related to habitual dietary patterns, in a general population. METHODS: This study was conducted in the framework of the Tehran Lipid and Glucose Study (2014-2017) on 1864 adult men and women. Urinary Na and K concentrations were measured in the morning spot urine samples. Dietary intakes of the participants were assessed using a validated 147-item Food Frequency Questionnaire (FFQ) and major dietary patterns were obtained using principal component analysis. Mediterranean dietary pattern and Dietary Approaches to Stop Hypertension (DASH) score, were also calculated. Multivariable-adjusted linear regression was used to indicate association of dietary patterns and urinary Na-to-K ratio. RESULTS: Mean (± SD) age of participants was 43.7 ± 13.9 years and 47% were men. Mean (± SD) urinary Na, K and the ratio was 139 ± 41.0 and 57.9 ± 18.6 mmol/L, 2.40 ± 0.07, respectively. Higher urinary Na-to-K ratio (> 2.37 vs. < 1.49) was related to lower intakes of vegetables (282 vs. 321 g/day), low-fat dairy (228 vs. 260 g/day) and fruits (440 vs. 370 g/day). Western dietary pattern was related to higher urinary Na-to-K ratio (ß = 0.06; 95% CI 0.01, 0.16). Traditional dietary pattern, Mediterranean and DASH diet scores were inversely associated with urinary Na-to-K ratio (ß = - 0.14; 95% CI - 0.24, - 0.11, ß = - 0.07; 95% CI - 0.09, - 0.01, ß = - 0.12; 95% CI - 0.05, - 0.02, respectively). CONCLUSIONS: Spot urinary Na-to-K ratio may be used as a simple and inexpensive method to monitor diet quality in population-based epidemiological studies.


Assuntos
Dieta/normas , Hipertensão/epidemiologia , Potássio/urina , Sódio/urina , Adulto , Feminino , Humanos , Hipertensão/prevenção & controle , Hipertensão/urina , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade
7.
Nitric Oxide ; 107: 58-65, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33340674

RESUMO

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.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Nitratos/farmacologia , Administração Oral , Beta vulgaris/química , Glicemia/análise , Peptídeo C/sangue , Peptídeo C/metabolismo , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , Feminino , Sucos de Frutas e Vegetais , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , Humanos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Nitratos/administração & dosagem , Óxido Nítrico/sangue , Óxido Nítrico/metabolismo , Raízes de Plantas/química
8.
Artigo em Inglês | MEDLINE | ID: mdl-32787767

RESUMO

AIM: In this study, we aimed to compare the pharmacokinetics of nitrate (NO3) in patients with type 2 diabetes mellitus (T2DM) and healthy adults. Potential effects of salivary nitrate reductase (NR) activity on cardiometabolic responses to an acute dose of NO3 was also assessed. METHODS: Nine healthy adults and nine T2DM patients were recruited to consume a NO3-rich breakfast (~410 mg NO3). Pharmacokinetics of NO3 were examined using repeated measurements of NOx (nitrate+ nitrite) concentrations of serum and saliva over 8 hours and NO3 concentrations of spot and 24-h urine samples. Cardiometabolic parameters, including serum levels of glucose, insulin, and triglycerides as well as blood pressure were also measured. RESULTS: Compared to patients with T2DM, serum NOx concentration (Δ1= 16.7 vs. 4.4 µmol/L, P=0.057) of healthy subjects sharply increased within 1 hour after NO3 loading. Healthy subjects had a higher NR activity index, and higher peak salivary NO3 concentration with a lower time to peak. Diabetic patients with high- compared to low-NR values had a higher whole-body NOx exposure (103±31.4 vs. 58.9±22.1 µmol.h/L); they also showed a better glycemic response and more reduction of blood pressure following ingestion of a NO3-rich meal. CONCLUSION: T2DM may be associated with a different pattern of NOx pharmacokinetics (especially salivary NOx metabolism). Salivary NR activity may have a critical role in postprandial metabolism of NO3, and diabetic patients with higher NR activity may take more advantages from NO3 supplementation.


Assuntos
Beta vulgaris , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/metabolismo , Nitratos/administração & dosagem , Nitratos/metabolismo , Nitritos/metabolismo , Adulto , Idoso , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saliva/metabolismo
9.
Nitric Oxide ; 103: 20-28, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32693171

RESUMO

PURPOSE: Decreased nitric oxide bioavailability in skin contributes to impaired wound healing in type 2 diabetes (T2D). This study aims at determining effects of acidified nitrite on wound closure as well as inflammatory and antioxidants markers in wound tissue of rats with T2D. MAIN METHODS: Skin wound was made on the back of rats 28 days after the induction of T2D (high-fat diet/low-dose of streptozotocin). Control and diabetic rats were subdivided into two subgroups: Untreated control (C), acidified nitrite-treated control (CN), untreated diabetes (D), and acidified nitrite-treated diabetes (DN). Acidified nitrite was applied once daily from day 3 to day 28 and the wounds were photographed for macroscopic changes. On days 3, 7, 14, 21, and 28 after wounding, wound levels of inflammatory and antioxidant markers were measured. RESULTS: Half closure time (CT50%) was significantly lower in acidified nitrite-treated diabetic rats compared to untreated ones (5.1 vs. 8.0 days, P < 0.001). Inflammatory response was delayed in diabetic rats and persistent inflammatory response was observed at day 14 after wounding. Acidified nitrite application restored the inflammatory response and antioxidant levels to control values. CONCLUSIONS: Acidified nitrite accelerated wound healing in rats with T2D by restoring delayed inflammatory response and augmentation of antioxidant defense.


Assuntos
Antioxidantes/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inflamação/tratamento farmacológico , Nitritos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/metabolismo , Concentração de Íons de Hidrogênio , Inflamação/induzido quimicamente , Inflamação/metabolismo , Masculino , Ratos , Ratos Wistar , Estreptozocina , Cicatrização/efeitos dos fármacos
10.
Naunyn Schmiedebergs Arch Pharmacol ; 393(6): 1103-1111, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31940052

RESUMO

Transient congenital hypothyroidism (TCH) has long-lasting consequences on the cardiovascular system during adulthood. The aim of this study was to determine whether nitric oxide (NO) and NO-producing enzymes are involved in impaired cardiac function as well as decreased tolerance to ischemia-reperfusion (IR) injury in adult male rats with TCH. Pregnant rats were divided into control and hypothyroid groups. Male offspring rats were categorized in control and hypothyroid (TCH) groups at week 16. Levels of NOx (nitrate+nitrite) and neuronal NOS (nNOS), inducible NOS (iNOS), and endothelial NOS (eNOS) were measured in hearts of rats and isolated perfused hearts from both groups were subjected to IR. Levels of NOx and NOSs were also measured in both groups after ischemia. Compared with controls, heart NOx levels were higher at baseline (48.0 ± 4.9 vs. 35.0 ± 2.6 µmol/L; P = 0.034) and following IR (103.6 ± 4.2 vs. 70.2 ± 2.7 µmol/L; P < 0.001) in rat with TCH. At baseline, compared with controls, heart iNOS and nNOS levels were significantly higher in rats with TCH (6.12 ± 0.34 vs. 4.78 ± 0.27 ng/mg protein; P = 0.008 for iNOS and 4.87 ± 0.28 vs. 3.55 ± 0.23 ng/mg protein; P = 0.003 for nNOS). Following IR, in rats with TCH, heart iNOS levels increased (11.75 ± 2.02 vs. 6.12 ± 0.34, ng/mg protein; P = 0.015) whereas nNOS level decreased (4.10 ± 0.25 vs. 4.87 ± 0.28 ng/mg protein; P = 0.063). Adverse effects of TCH on cardiac function are associated with increased ratio of iNOS/eNOS; in addition, increased heart nNOS levels are involved in impaired cardiac function while its decrease is associated with decreased tolerance to IR injury.


Assuntos
Hipotireoidismo Congênito/fisiopatologia , Coração/fisiopatologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Óxido Nítrico Sintase/fisiologia , Animais , Feminino , Hemodinâmica , Masculino , Óxido Nítrico Sintase/análise , Ratos , Ratos Wistar , Hormônios Tireóideos/sangue
11.
Life Sci ; 230: 188-196, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31150686

RESUMO

AIMS: Hyperoxia has beneficial metabolic effects in type 2 diabetes. However, hyperoxia exacerbates already existing oxidative stress in type 2 diabetes. Nitrate, a nitric oxide donor, is an effective new treatment in type 2 diabetes and also has antioxidant properties. The aim of this study was to determine whether nitrate administration can attenuate hyperoxia-induced oxidative stress in obese type 2 diabetic rats. MAIN METHODS: Fifty-six male Wistar rats (190-210 g) were divided into 8 groups: Controls (non-treated, nitrate-treated, O2-treated, and nitrate + O2-treated) and diabetes (non-treated, nitrate-treated, O2-treated, and nitrate + O2-treated). Diabetes was induced using high-fat diet and low-dose of streptozotocin (30 mg/kg). Rats in intervention groups, were exposed to 95% oxygen and consumed sodium nitrate (100 mg/L) in drinking water. Serum fasting glucose, oxidized (GSSG) and reduced (GSH) glutathiones, total oxidant status (TOS), catalase and superoxide dismutase (SOD) activities, and total antioxidant capacity (TAC) were measured after intervention. Oxidative stress index (OSI) was calculated as TOS/TAC ratio. KEY FINDINGS: Diabetic rats had increased oxidative stress and hyperoxia exacerbated it. In O2-diabetic rats, nitrate decreased GSSG (102.7 ±â€¯2.1 vs. 236.0 ±â€¯20.1 µM, P < 0.001), TOS (67.7 ±â€¯7.3 vs. 104 ±â€¯3.8 µM, P < 0.001), and OSI (0.44 ±â€¯0.04 vs. 0.91 ±â€¯0.07, P < 0.001) and increased catalase (2.8 ±â€¯0.13 vs. 1.8 ±â€¯0.21 KU/L, P = 0.014), SOD (53.4 ±â€¯1.5 vs. 38.4 ±â€¯1.2 U/mL, P < 0.001), GSH (43.7 ±â€¯1.4 vs. 17.8 ±â€¯0.5 mM, P = 0.003), TAC (152.5 ±â€¯1.9 vs. 116.7 ±â€¯5.0 mM, P < 0.001), and GSH/GSSG ratio (0.43 ±â€¯0.01 vs. 0.08 ±â€¯0.01, P = 0.005). Nitrate also potentiated effects of hyperoxia on decreasing fasting glucose. SIGNIFICANCE: Our results showed that dietary nitrate attenuates hyperoxia-induced oxidative stress in type 2 diabetic rats.


Assuntos
Nitratos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Glicemia/análise , Catalase/análise , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Glucose/metabolismo , Glutationa/análise , Hiperóxia/tratamento farmacológico , Hiperóxia/metabolismo , Masculino , Nitratos/metabolismo , Obesidade/complicações , Obesidade/metabolismo , Ratos , Ratos Wistar , Superóxido Dismutase/análise
12.
Life Sci ; 220: 58-68, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30703383

RESUMO

AIMS: Type 2 diabetes and obesity are associated with chronic hypoxia, which contributes to adipose tissue dysfunction and development of insulin resistance and metabolic disorders. We assessed long-term effects of hyperoxia on browning of adipocytes and carbohydrate metabolism in a murine model of type 2 diabetes. MAIN METHODS: Male Wistar rats (190-210 g) were divided into 4 groups: Control, O2-treated control, untreated diabetes, and O2-treated diabetes. Diabetes was induced using high-fat diet followed by a low-dose of streptozotocin (30 mg/kg). Hyperoxia sessions were included 2-h exposure to 95% oxygen, repeated 6 days/week for 5 weeks. Serum fasting glucose, insulin, lactate, and lipid profile were measured before, during, and after hyperoxia. Glucose and pyruvate tolerance tests, and histological evaluations of interscapular and epididymal fats were done at the end of study. KEY FINDINGS: O2-treated diabetic rats compared to untreated ones, displayed lower weight gain, improved glucose-tolerance, insulin sensitivity, and more favorable lipid profile. In diabetic rats, hyperoxia increased surface area (6.36 ±â€¯0.93 vs. 0.86 ±â€¯0.16 mm2, P < 0.001), and volume density (1.53 ±â€¯0.22 vs. 0.21 ±â€¯0.04 mm3, P < 0.001) of interscapular adipose tissue; hyperoxia also increased protein levels of uncoupling protein 1 (UCP1), peroxisome proliferator activated receptor gamma (PPAR-γ), and PPAR-γ coactivator 1 alpha (PGC1-α) in interscapular adipose tissue. The numerical density (541.7 ±â€¯7.3 vs. 298.1 ±â€¯11.7 mm3, P < 0.001) of epididymal fat were also higher. SIGNIFICANCE: This study showed that beneficial metabolic effects of hyperoxia in obese type 2 diabetic rats including improved insulin sensitivity and glucose tolerance are at least in part due to browning of adipose tissue.


Assuntos
Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Hiperóxia/metabolismo , Adipócitos Marrons , Adipócitos Brancos , Animais , Metabolismo dos Carboidratos/fisiologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Glucose/metabolismo , Teste de Tolerância a Glucose , Insulina/metabolismo , Resistência à Insulina , Masculino , Obesidade/metabolismo , Ratos , Ratos Wistar , Estreptozocina/farmacologia
13.
Crit Rev Oncog ; 24(3): 213-222, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32422019

RESUMO

The prevalence of type 2 diabetes (T2D) is increasing worldwide. This study provides essential information about the classification, diagnosis, pathogenesis, treatment, and complications of T2D. Glucose homeostasis is controlled by the rates of endogenous glucose production (EGP) and glucose utilization. EGP is ~2 mg/kg/min in humans and is equal to the rate of basal glucose utilization. During fasting, ~75-85% of EGP occurs in the liver and the remainder in the kidney. Hepatic glucose production is the main determinant of fasting blood glucose concentration. In the fed state, when insulin secretion is stimulated and glucagon secretion is inhibited, EGP decreases and glucose uptake in splanchnic (liver and gut) and peripheral (primarily muscle) tissues increases. ß-cell dysfunction and insulin resistance represent core pathophysiological defects in T2D. Although the pathogenesis of T2D was previously focused on dysfunctions of "ominous triumvirate" (liver, skeletal muscle, and ß-cell), it has been extended to "ominous octet," which includes defects in adipocytes (increased lipolysis), gastrointestinal tract (incretin deficiency/resistance), pancreatic α-cells (hyperglucagonemia), kidneys (increased glucose reabsorption), and brain (insulin resistance); endothelial dysfunction, inflammation, increased oxidative stress, and hypoxia are also involved in the pathogenesis of T2D. In conclusion, diabetes is one of the leading causes of morbidity and mortality worldwide. More insights into the pathophysiology of T2D necessitate revising the treatment approaches from only glycemic control to a pathophysiological-based view. In addition, new emerging complications of T2D such as cancer warrant further attention.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Resistência à Insulina/fisiologia , Humanos , Fígado/metabolismo , Fígado/patologia , Pâncreas/metabolismo , Pâncreas/patologia , Fatores de Risco
14.
Sci Total Environ ; 635: 308-314, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29665547

RESUMO

Oil fields are a source of heavy metal pollution, but few studies have evaluated its impact on the intake of these contaminants through milk, an important food especially for children. From February 2015 to 2016, 118 samples of raw cow's milk, 14 of fodder and 8 of water in Southwest Iran were collected from farms close to oil fields or related industries. Lead (Pb) and cadmium (Cd) levels were evaluated by graphite furnace atomic absorption spectrometry. Mean±SE in milk and fodder were 47.0±3.9 and 54.0±6.9µg/kg for Pb, and 4.7±1.0 and 3.5±1.3µg/kg for Cd. No Pb or Cd was detected in water. Most milk samples (82.2%) for Pb were above the permissible limits (20µg/kg). Exposure to Pb and Cd from milk consumption was calculated in two scenarios: mean and maximum exposure for the age range of 2-90years. The intake of an average Iranian adult (25years, 60kg b. w., 0.14kg milk/day) would be 6.6µg Pb and 0.66µg Cd/day (WI of 46.2 and 4.6µg, respectively), well below the risk values proposed by some international organizations, even in the maximum exposure scenario. However, Pb exposure for infants and toddlers may be closer to the risk values, since milk and milk products could be the main contributor to Cd and Pb, and small children consume 2-3 times more food than adults relative to their body weight. The risk of Pb and Cd exposure through milk close to oil fields should be considered and a monitoring plan for these contaminants is strongly recommended.


Assuntos
Cádmio/análise , Exposição Dietética/estatística & dados numéricos , Poluentes Ambientais/análise , Contaminação de Alimentos/estatística & dados numéricos , Leite/química , Animais , Bovinos , Contaminação de Alimentos/análise , Humanos , Irã (Geográfico) , Indústria de Petróleo e Gás , Medição de Risco
15.
Oxid Med Cell Longev ; 2017: 5350267, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28607631

RESUMO

The prevalence of obesity and diabetes is increasing worldwide. Obesity and diabetes are associated with oxidative stress, inflammation, endothelial dysfunction, insulin resistance, and glucose intolerance. Obesity, a chronic hypoxic state that is associated with decreased nitric oxide (NO) bioavailability, is one of the main causes of type 2 diabetes. The hypoxia-inducible factor-1α (HIF-1α) is involved in the regulation of several genes of the metabolic pathways including proinflammatory adipokines, endothelial NO synthase (eNOS), and insulin signaling components. It seems that adipose tissue hypoxia and NO-dependent vascular and cellular dysfunctions are responsible for other consequences linked to obesity-related disorders. Although hyperoxia could reverse hypoxic-related disorders, it increases the production of reactive oxygen species (ROS) and decreases the production of NO. Nitrate can restore NO depletion and has antioxidant properties, and recent data support the beneficial effects of nitrate therapy in obesity and diabetes. Although it seems reasonable to combine hyperoxia and nitrate treatments for managing obesity/diabetes, the combined effects have not been investigated yet. This review discusses some aspects of tissue oxygenation and the potential effects of hyperoxia and nitrate interventions on obesity/diabetes management. It can be proposed that concomitant use of hyperoxia and nitrate is justified for managing obesity and diabetes.


Assuntos
Hipóxia Celular/genética , Diabetes Mellitus Tipo 2/complicações , Hiperóxia/metabolismo , Inflamação/metabolismo , Nitratos/metabolismo , Obesidade/complicações , Estresse Oxidativo
16.
Eur J Ophthalmol ; 27(1): 109-112, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27228971

RESUMO

Purpose To determine the prevalence of amblyopia, strabismus, and ptosis among schoolchildren in Dezful in the west of Iran. Methods In this cross-sectional study, 1,375 schoolchildren of Dezful were selected through multistage cluster sampling. After obtaining written consents, participants had uncorrected and corrected visual acuity tests, cycloplegic refraction, and the cover test, and were examined for ptosis at the school site. Results Of the 1,151 study participants (83.7%), examinations were completed for 1,130 schoolchildren. Prevalence rates of amblyopia, strabismus, and ptosis were 2.7% (95% confidence interval [CI] 0.8-4.7), 1.9% (95% CI: 0.2-3.8), and 0.8%, respectively. Anisometropia was the most common cause of amblyopia; 45.2% of cases had anisometropic amblyopia. Among cases with strabismus, 63.6% were exotropic and 36.4% were esotropic. Conclusion The present study indicated that the prevalence of amblyopia and strabismus in Dezful schoolchildren falls in the average range. Since the Amblyopia Screening Program has been running for years, we expected lower rates compared to previous years, but this was not observed. Correcting refractive errors can significantly reduce amblyopic cases.

17.
Iran Red Crescent Med J ; 17(8): e26946, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26430526

RESUMO

BACKGROUND: Urinary tract infection (UTI) is the most common disorder caused by bacterial agents in pregnancy, which can lead to important complications in newborn of such mothers in case of inappropriate diagnosis and treatment. OBJECTIVES: The purpose of this study was to study the prevalence of UTI among pregnant women and its complications in their newborns during the birth in the hospitals of Dezful City, Iran, during 2012 - 2013. PATIENTS AND METHODS: In this cross-sectional retrospective study, 1132 women admitted to Dr. Ganjavian and Ayatollah Nabavi Hospitals in Dezful City, Iran, during 2012 - 2013 were randomly allocated into the case and control groups and were matched based on their age, numbers of pregnancy, sex and diseases of their children. UTI was the only difference between the two groups. RESULTS: Twenty-two thousand six hundred deliveries occurred within the course of this study. Due to UTI, 5% of deliveries led to hospitalization of mothers (1132 patients).Weight and height of newborn infants of mothers afflicted with UTI (P < 0.001) were significantly lower compared to newborns of healthy women (P < 0.001). There was a significant association between the two groups of pregnant women with UTI in terms of type of delivery (normal and caesarean section) (P < 0.008). CONCLUSIONS: The lower incidence of UTI in pregnant women compared to other areas of Iran represents the role of climate and weather in the prevalence of UTI. In addition, the increased number of low-birth-weight infants had a remarkable correlation with UTI, which can influence the health of the next generation.

18.
J Curr Ophthalmol ; 27(1-2): 51-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27239576

RESUMO

PURPOSE: To determine the prevalence of refractive errors, among 6- to 15-year-old schoolchildren in the city of Dezful in western Iran. METHODS: In this cross-sectional study, 1375 Dezful schoolchildren were selected through multistage cluster sampling. After obtaining written consent, participants had uncorrected and corrected visual acuity tests and cycloplegic refraction at the school site. Refractive errors were defined as myopia [spherical equivalent (SE) -0.5 diopter (D)], hyperopia (SE ≥ 2.0D), and astigmatism (cylinder error > 0.5D). RESULTS: 1151 (83.7%) schoolchildren participated in the study. Of these, 1130 completed their examinations. 21 individuals were excluded because of poor cooperation and contraindication for cycloplegic refraction. Prevalence of myopia, hyperopia, and astigmatism were 14.9% (95% confidence interval (CI): 10.1-19.6), 12.9% (95% CI: 7.2-18.6), and 45.3% (95% CI: 40.3-50.3), respectively. Multiple logistic regression analysis showed an age-related increase in myopia prevalence (p << 0.001) and a decrease in hyperopia prevalence (p << 0.001). There was a higher prevalence of myopia in boys (p<<0.001) and hyperopia in girls (p = 0.007). CONCLUSION: This study showed a considerably high prevalence of refractive errors among the Iranian population of schoolchildren in Dezful in the west of Iran. The prevalence of myopia is considerably high compared to previous studies in Iran and increases with age.

19.
Acta Ophthalmol ; 93(1): e74-81, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25043552

RESUMO

PURPOSE: To determine the distribution of ocular biometric components and their correlation with age and sex during the ages of ocular development in a 6- to 18-year-old population in Iran. METHOD: In this cross-sectional study, which was performed in October 2012, multi-stage stratified cluster sampling was used to sample the study population from Dezful schools, a city in the southwest of Iran. Biometric examinations were done by an experienced optometrist using the LENSTAR/BioGraph (WaveLight AG, Erlangen, Germany). RESULTS: Among 864 selected students, 683 participated in the study (response rate: 79.1%); 377 participants (55.2%) were male, and the mean age of the participants was 12 ± 3.4 years (range: 6-18 years). The mean and 95% confidence interval of axial length (AL) were 23.13 mm (22.93-23.33), anterior chamber depth (ACD) was 3.01 mm (2.96-3.06), lens thickness (LT) was 3.58 mm (3.55-3.61), central corneal thickness (CCT) was 549.33 mic (546.59-552.07), corneal radius (CR) was 7.77 mm (7.74-7.81), corneal diameter (CD) was 12.34 mm (12.31-12.38) and pupil diameter (PD) was 4.97 (4.91-5.03). Mean AL, ACD, CD and CR were significantly higher in boys, and mean LT was significantly higher in girls. AL and ACD increased, while LT decreased significantly with age. Myopia was associated with an increase in AL and ACD, and hyperopia was associated with an increase in LT and a decrease in ACD. CONCLUSION: This study evaluated the distribution of the biometric components of the eye during the ages of ocular development in an Iranian population. In this age range, the majority of the changes were observed in the AL and LT.


Assuntos
Câmara Anterior/anatomia & histologia , Comprimento Axial do Olho/anatomia & histologia , Córnea/anatomia & histologia , Olho/crescimento & desenvolvimento , Cristalino/anatomia & histologia , Pupila , Adolescente , Biometria , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Tamanho do Órgão , Fatores Sexuais
20.
Iran Red Crescent Med J ; 16(8): e10016, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25389468

RESUMO

BACKGROUND: Road traffic injuries are among the leading causes of death in the world and Iran. OBJECTIVES: The aim of this study was to assess the role of age, sex, education, and time of accident on human casualties and mortalities of road crashes in Iran. MATERIALS AND METHODS: This study was based on data gathered by Iranian Police Department from the records of road crashes from April 4, 2008 through April 4, 2009. Road crashes are categorized into three types: with no human casualties, with injuries, and with human mortalities. RESULTS: The largest rate of human causalities was observed in people aged between 25 to 34 years (P < 0.001). Illiterate people had 81% smaller odds of causality in road crashes (P < 0.001) in comparison with those with a kind of academic education. Overall, 73.4% of crashes had happened during the last ten days of a month were with human casualties (P < 0.001) and human casualties rate was slightly higher in crashes happened between 1 AM to 5 AM Fatality rate was slightly higher in the females (OR = 2.6, P = 0.068). The smallest odds of fatality were found in the people aged between 18 to 24 years and the highest odds were seen in people ≥ 55 years of age (P < 0.001). In people with a university education, 61.9% of crashes were with fatality (P = 0.026). In addition, 82.8% of crashes during winter, 60.2% of crashes during autumn, and 35.8% of crashes during summer were with mortalities. Overall, 78.3% of crashes with human casualties that had happened during 1 AM to 5 AM led to mortalities. There was also a significant association between injury and its intensity with fastening seatbelts. CONCLUSIONS: Older age, university degrees, female sex, wintertime, and the time of accident seem to be the most important risk factors in road crashes that lead to fatalities in Iran. Drivers in Iran should be informed and trained regarding these risk factors, which have direct effect on casualties and mortalities in road crashes.

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