Effect of voluntary exercise on intracellular signalling pathways of angiogenesis in the sciatic nerve of type 1 diabetic castrated male rats.

OBJECTIVES: Impaired angiogenesis in sciatic nerve is a major complication of diabetic neuropathy. Protein kinase B (AKT) and extracellular signal regulated kinase (ERK) signaling pathways play critical roles during capillary-like network formation in the angiogenesis process. METHODS: Twenty-four adult male Wistar rats (weight: 250-300 g) were used in the research. The rats were randomly divided into four groups (n = 6): (1) diabetic (Dia), (2) diabetic + castration (Dia-Cas), (3) diabetic + exercise (Dia-E), and (4) diabetic + castration + exercise (Dia-Cas-E). Type 1 diabetes (T1D) was induced with streptozotocin (50 mg/kg). After 6 weeks, sciatic nerve was separated and used for histological evaluation and determination of phosphorylated AKT (P-AKT) and phosphorylated ERK (P-ERK) levels by ELISA method. RESULTS: Glucose levels decreased in the Dia-E group compared to the Dia-Cas group (p < 0.01). In addition, our finding shows that exercise in the Dia-Cas group diminished blood glucose levels compared to the Dia-Cas group but this effect of exercise was not significant. Voluntary exercise in the diabetic castrated group decreased P-AKT protein and increased P-ERK 1/2 protein levels in the sciatic tissue compared to the diabetes group significantly (p < 0.05). Histopathological findings showed that Dia-Cas group with 6-week exercise training significantly raised the number of microvascular density in the sciatic tissue of diabetic rats compared to the diabetic group (p < 0.05). CONCLUSIONS: Voluntary exercise in diabetic rats increases angiogenesis in the sciatic nerve. The possible mechanism is the increase of P-ERK 1/2 but not P-AKT levels in the sciatic nerve of T1D rats.

CARDIO-RENAL METABOLIC SYNDROME AND PRO-INFLAMMATORY FACTORS: THE DIFFERENTIAL EFFECTS OF DIETARY CARBOHYDRATE AND FAT.

BACKGROUND: We aimed to evaluate whether a high carbohydrate or a high fat diet differs in alteration of the inflammatory and metabolic risk factors in cardio-renal metabolic syndrome in rats. METHODS: Twelve male Wister rats were randomly divided into two groups: one received diet 1 standard pellet rat diet (D1) containing 10% fat, 50% carbohydrate, 25% protein and another group received diet 2 (D2) containing 59% fat, 30% carbohydrate and 11% protein for 16 weeks. Weight was recorded weekly. FSG and insulin levels were measured using an enzymatic spectrophotometric and a standard ELISA kit respectively. Inflammatory parameters including TGF-ß, MCP-1, TNF-α, IL-1ß, IL-6 in the renal and cardiac tissues of rats were evaluated by ELISA technique. RESULT: Food intake in D1 and D2 groups increased in the study period, however food intake in D2 group was significantly higher compared with D1 group. FSG, HOMA and TG concentrations in D2 group were significantly higher compared to D1 group. Moreover, TGF-ß and MCP-1 concentrations in the renal tissues of D2 group and TNF-α in the cardiac tissues of D1 group were significantly higher compared with D1 group (P<0.05). Positive associations between IL-1ß and TG and between HOMA, FSG with TGF-ß and MCP-1 in the renal tissue of animals were also identified.

Vitamin D administration, cognitive function, BBB permeability and neuroinflammatory factors in high-fat diet-induced obese rats.

OBJECTIVES: The purpose of this research was to investigate the effects of vitamin D administration on cognitive function, nuclear factor-κB (NF-κB), brain-derived neurotrophic factor (BDNF) concentration in the hippocampus and blood-brain barrier (BBB) permeability in high-fat diet (HFD)-induced obese rats. METHODS: Male Wistar rats were fed either a control diet or HFD for 16 weeks (n=20); then, each group was randomized into two subgroups supplemented orally with 500 IU kg-1 vitamin D for 5 weeks. A Morris water maze (MWM) test was performed at the 21st week to examine cognitive function. BBB permeability was characterized by Evans blue dye in the hippocampus. BDNF and NF-κB concentrations in the hippocampus and serum vitamin D concentrations were also measured. RESULTS: HFD led to a significant delay in escape latency time and reduced time of MWM probe test because of increased NF-κB and decreased BDNF concentrations in the hippocampus. Vitamin D supplementation in the HFD group significantly reduced body weight, NF-κB concentrations, BBB permeability and increased BDNF concentrations in the hippocampus. CONCLUSIONS: Vitamin D reversed HFD-induced cognitive impairments by reduction of the NF-κB and elevation of BDNF concentrations and modulation of the BBB permeability in rats' hippocampus.

Bilateral diffuse pulmonary infiltration in a heart transplant recipient.

Pulmonary complications are not infrequent after heart transplantation. Kaposi sarcoma is a vascular tumor that can involve the skin as well as visceral organs. We describe a case of visceral and cutaneous Kaposi sarcoma that presented with diffuse bilateral pulmonary infiltration and breathlessness 6 month after heart transplantation. Following modulation of the immunosuppressive regimen and addition of chemotherapy, the patient had an excellent response and has had an uneventful 1-year follow-up.

Comparing results of digital photoplethysmography in two groups of chronic obstructive pulmonary disease patients with and without high pulmonary artery pressure.

BACKGROUND: Digital photoplethysmography (D-PPG) is a newly introduced method of optical screening of deep vein thrombosis (DVT) by recording changes in the size of limb due to tissue fluid. OBJECTIVES: The objective of this study is to assess the effect of high pulmonary artery pressure (PAP) and consequently increased venous system pressure on D-PPG test results. METHODS: Forty-five patients with and 45 patients without PAP pressure were enrolled in the study and divided into two groups. All the patients had a history of chronic obstructive pulmonary disease (COPD). D-PPG test was performed for both legs of all the patients and the results of the two groups were compared. Also, all patients underwent duplex sonography for ruling out DVT. RESULTS: Using venous refilling time (RT) of <22 s as the optimal cut-off point, it was found that 32 (35%) legs of patients with and 39 (43%) legs of patients without high PAP had positive D-PPG test. Although the rate of positive D-PPG test was higher in patients with high PAP, this was not statistically significant (P = 0.28). Moreover, overall correlation between RT and venous pump detected by D-PPG and PAP was r = -0.11 (P = 0.2) and r = -0.01 (P = 0.6), respectively. CONCLUSION: Our results showed that the rate of positive D-PPG test results is slightly higher in patients with pulmonary hypertension, but this difference is not statistically significant. Therefore, increased PAP could be excluded as a confounding factor of D-PPG test.