Diabetes as a Pancreatic Microvascular Disease-A Pericytic Perspective.

Diabetes is not only an endocrine but also a vascular disease. Vascular defects are usually seen as consequence of diabetes. However, at the level of the pancreatic islet, vascular alterations have been described before symptom onset. Importantly, the cellular and molecular mechanisms underlying these early vascular defects have not been identified, neither how these could impact the function of islet endocrine cells. In this review, we will discuss the possibility that dysfunction of the mural cells of the microvasculature-known as pericytes-underlies vascular defects observed in islets in pre-symptomatic stages. Pericytes are crucial for vascular homeostasis throughout the body, but their physiological and pathophysiological functions in islets have only recently started to be explored. A previous study had already raised interest in the "microvascular" approach to this disease. With our increased understanding of the crucial role of the islet microvasculature for glucose homeostasis, here we will revisit the vascular aspects of islet function and how their deregulation could contribute to diabetes pathogenesis, focusing in particular on type 1 diabetes (T1D).

Central blood pressure and aortic pulse wave reflection in water-exercised postmenopausal hypertensive women: A cross-sectional study.

Exercise training has been associated with the attenuation of cardiovascular impairment after menopause. This study aimed to compare central and peripheral blood pressure and aortic pulse wave reflection in sedentary and trained (aerobic exercise in the water) hypertensive postmenopausal women. Hypertensive postmenopausal women were divided into sedentary (SED, n = 53) and trained groups (TR, n = 31). Self-reporting from the trained group presented a mean of 1.7 ± 0.3 years of exercise practice in the water. Central blood pressure and amplification indexes (AIx) were obtained by the applanation tonometry of radial and aortic arteries. No changes were observed in systolic blood pressure (SBP) in the TR group than the SED group; however, office diastolic blood pressure (DBP) was reduced compared to the SED group. Central blood pressure and augmentation index (AIx@75%) values were similar in the SED and TR groups. These data suggest that self-reported long-term exercise training in the water could not improve central hemodynamic variables in postmenopausal hypertensive women compared to sedentary ones. However, it should be emphasized that DBP levels were reduced in trained subjects, which might reduce cardiovascular outcomes.

Combined Aerobic and Resistance Exercises Evokes Longer Reductions on Ambulatory Blood Pressure in Resistant Hypertension: A Randomized Crossover Trial.

AIM: The present study compared the acute effects of aerobic (AER), resistance (RES), and combined (COM) exercises on blood pressure (BP) levels in people with resistant hypertension (RH) and nonresistant hypertension (NON-RH). METHODS: Twenty patients (10 RH and 10 NON-RH) were recruited and randomly performed three exercise sessions and a control session. Ambulatory BP was monitored over 24 hours after each experimental session. RESULTS: Significant reductions on ambulatory BP were found in people with RH after AER, RES, and COM sessions. Notably, ambulatory BP was reduced during awake-time and night-time periods after COM. On the other hand, the effects of AER were more prominent during awake periods, while RES caused greater reductions during the night-time period. In NON-RH, only RES acutely reduced systolic BP, while diastolic BP was reduced after all exercise sessions. However, the longest postexercise ambulatory hypotension was observed after AER (~11 h) in comparison to RES (~8 h) and COM (~4 h) exercises. CONCLUSION: Findings of the present study indicate that AER, RES, and COM exercises elicit systolic and diastolic postexercise ambulatory hypotension in RH patients. Notably, longer hypotension periods were observed after COM exercise. In addition, NON-RH and RH people showed different changes on BP after exercise sessions, suggesting that postexercise hypotension is influenced by the pathophysiological bases of hypertension.

Exercise benefits the cardiac, autonomic and inflammatory responses to organophosphate toxicity.

The organophosphate, diisopropyl fluorophosphate (DFP), may impair cardiovascular, autonomic and immune function while exercise training is thougt to be restorative. Experiments determined effects of wheel exercise in C57B1 male mice, testing cardiovascular and autonomic function and characterization of the immunological profile. Sedentary (S) and exercise (ET) groups were treated with corticosterone (CORT) followed by injection of DFP. This model was associated with systolic and diastolic dysfunction in the S group, measured using echocardiography (ECHO). Chronic exercise ameliorated the cardiac deficit. Autonomic balance, accessed by heart rate variability (HRV), showed increased sympathetic and decreased parasympathetic modulation in S group. Autonomic balance in ET mice was not affected by DFP. Our DFP model resulted in mild neuroinflammation seen by increased IL5, IL12 and MIP2 in brain and plasma IL6 and IL1a. DFP had a negative impact on cardiac/autonomic function and inflammatory markers, effects reduced by exercise. Data suggest a beneficial effect of exercise training on the cardiovascular and autonomic responses to DFP/CORT.