Afferent innervation of the ischemic kidney contributes to renal dysfunction in renovascular hypertensive rats.

The ablation of renal nerves, by destroying both the sympathetic and afferent fibers, has been shown to be effective in lowering blood pressure in resistant hypertensive patients. However, experimental studies have reported that the removal of sympathetic fibers may lead to side effects, such as the impairment of compensatory cardiorenal responses during a hemodynamic challenge. In the present study, we evaluated the effects of the selective removal of renal afferent fibers on arterial hypertension, renal sympathetic nerve activity, and renal changes in a model of renovascular hypertension. After 4 weeks of clipping the left renal artery, afferent renal denervation (ARD) was performed by exposing the left renal nerve to a 33 mM capsaicin solution for 15 min. After 2 weeks of ARD, we found reduced MAP (~ 18%) and sympathoexcitation to both the ischemic and contralateral kidneys in the hypertensive group. Moreover, a reduction in reactive oxygen species was observed in the ischemic (76%) and contralateral (27%) kidneys in the 2K1C group. In addition, ARD normalized renal function markers and proteinuria and podocin in the contralateral kidney. Taken altogether, we show that the selective removal of afferent fibers is an effective method to reduce MAP and improve renal changes without compromising the function of renal sympathetic fibers in the 2K1C model. Renal afferent nerves may be a new target in neurogenic hypertension and renal dysfunction.

Retroperitoneal adipose tissue denervation improves cardiometabolic and autonomic dysfunction in a high fat diet model.

Sympathetic vasomotor overactivity is a major feature leading to the cardiovascular dysfunction related to obesity. Considering that the retroperitoneal white adipose tissue (rWAT) is an important fat visceral depot and receives intense sympathetic and afferent innervations, the present study aimed to evaluate the effects evoked by bilateral rWAT denervation in obese rats. Male Wistar rats were fed with HFD for 8 consecutive weeks and rWAT denervation was performed at the 6th week. Arterial pressure, splanchnic and renal sympathetic vasomotor nerve activities were assessed and inflammation and the components of the renin -angiotensin system were evaluated in different white adipose tissue depots. HFD animals presented higher serum levels of leptin and glucose, an increase in arterial pressure and splanchnic sympathetic nerve activity; rWAT denervation, normalized these parameters. Pro-inflammatory cytokines levels were significantly increased, as well as RAAS gene expression in WAT of HFD animals; rWAT denervation significantly attenuated these changes. In conclusion, HFD promotes vasomotor sympathetic overactivation and inflammation with repercussions on the cardiovascular system. In conclusion, the neural communication between WAT and the brain is fundamental to trigger sympathetic vasomotor activation and this pathway is a possible new therapeutic target to treat obesity-associated cardiovascular dysfunction.

Selective afferent renal denervation mitigates renal and splanchnic sympathetic nerve overactivity and renal function in chronic kidney disease-induced hypertension.

BACKGROUND: Clinical and experimental evidence have shown that renal denervation, by removing both the sympathetic and afferent nerves, improves arterial hypertension and renal function in chronic kidney disease (CKD). Given the key role of renal sympathetic innervation in maintaining sodium and water homeostasis, studies have indicated that the total removal of renal nerves leads to impaired compensatory mechanisms during hemodynamic challenges. METHOD: In the present study, we hypothesized that afferent (or sensory) fibers from the diseased kidney contribute to sympathetic overactivation to the kidney and other target organ, such as the splanchnic region, contributing to hypertension in CKD. We used a method to remove selectively the afferent renal fibers (periaxonal application of 33 mmol/l capsaicin) in a rat model of CKD, the 5/6 nephrectomy. RESULTS: Three weeks after afferent renal denervation (ARD), we found a decrease in mean arterial pressure (∼15%) and normalization in renal and splanchnic sympathetic nerve hyperactivity in the CKD group. Interestingly, intrarenal renin--angiotensin system, as well as renal fibrosis and function and proteinuria were improved after ARD in CKD rats. CONCLUSION: The findings demonstrate that afferent fibers contribute to the maintenance of arterial hypertension and reduced renal function that are likely to be mediated by increased sympathetic nerve activity to the renal territory as well as to other target organs in CKD.

Masticatory function, taste, and salivary flow in young healthy adults.

This study aimed to investigate masticatory function and taste and their possible relationship with salivary flow in young adults with good oral health. The study also examined whether anthropometric measurements and gender could influence the variables studied. A total of 171 subjects were selected (125 females, 46 males). Masticatory performance was evaluated with the sieve method, and perceived masticatory ability was measured using the visual analogue scale. Taste was evaluated using the drop test with four different flavors in three different concentrations, and unstimulated and stimulated saliva flows were measured. The anthropometric variables measured included body mass index (BMI) and waist circumference (WC). The independent variables studied could not predict masticatory performance. The independent variables, BMI, WC, and gender, predicted 14% of perceived masticatory ability, and BMI predicted 5% of taste. Masticatory performance was not related to salivary flow or anthropometric parameters in young healthy adults. Perceived masticatory ability was related to BMI, WC, and gender, whereas taste was only weakly related to BMI. The flow rate did not exhibit a statistically significant difference between males and females for the anthropometric groups. (J Oral Sci 58, 391-399, 2016).

Vertical dimension of the face analyzed by digital photographs.

Esthetics is a primary consideration for patients seeking prosthodontic treatment. The alteration of the facial vertical dimension can deteriorate the orofacial harmony. When it is essential to assess dentofacial attractiveness, there is a consensus in the research community that the soft tissue evaluation in digital photographs is much more consistent than the traditional cephalometric analyses. The aim of this study was to compare the lower third of the face with the facial segment (ie, the distance between the outer cantus of the eye and the labial commissural), to verify whether or not there are statistical correlations and significant differences between them. Front-view standardized digital photographs of 84 dentate Brazilian subjects were used to measure all facial segments through an image-processing program. The Student ttest showed no significant difference between the left facial segment and the lower third of the face. Pearson's product-moment coefficient showed significant correlations between both facial segments and the lower third of the face. After the regression analysis, two mathematical equations were used to correlate the facial segment to the lower third of the face. The distance between the outer cantus of the eye and the labial commissurae can be a reliable guide to estimate the vertical dimension of the rest position. Moreover, when it is measured on the left side of the face there is a better chance to correctly estimate the appropriate size.