Impacts of High Fructose Diet and Chronic Exercise on Nitric Oxide Synthase and Oxidative Stress in Rat Kidney

Chronic exercise (Ex) exerts antihypertensive and renoprotective effects in rats fed a high fructose diet (HFr). To elucidate the mechanisms, the impacts of an HFr and Ex on the nitric oxide (NO) system and oxidative stress in the kidney were examined. Rats were fed a control diet or an HFr, and a part of the HFr-fed rats underwent treadmill running for 12 weeks. The HFr did not affect nitrate/nitrite (NO_x) levels in plasma and urine, and Ex increased the NO_x levels. The HFr increased thiobarbituric acid reactive substance (TBARS) levels in plasma and urine, and Ex decreased the HFr-increased TBARS levels in plasma. The HFr increased the neuronal and endothelial NO synthase (nNOS and eNOS) expressions, and Ex enhanced the HFr-increased eNOS expression. The HFr inhibited the eNOS phosphorylation at serine 1177, and Ex restored the HFr-inhibited eNOS phosphorylation. The HFr increased xanthine oxidase and NADPH oxidase activities, and Ex restored the HFr-increased xanthine oxidase activity but enhanced the HFr-increased NADPH oxidase activity. The HFr increased the nitrotyrosine levels, and Ex attenuated the HFr-increased levels. These results indicate that although Ex enhances the HFr-increased eNOS expression and NADPH oxidase activity, an HFr inhibits renal eNOS phosphorylation and NO bioavailability, whereas Ex ameliorates them.

Pentadecapeptide BPC 157 and the central nervous system

We reviewed the pleiotropic beneficial effects of the stable gastric pentadecapeptide BPC 157, three very recent demonstrations that may be essential in the gut-brain and brain-gut axis operation, and therapy application in the central nervous system disorders, in particular. Firstly, given in the reperfusion, BPC 157 counteracted bilateral clamping of the common carotid arteries-induced stroke, sustained brain neuronal damages were resolved in rats as well as disturbed memory, locomotion, and coordination. This therapy effect supports particular gene expression in hippocampal tissues that appeared in BPC 157-treated rats. Secondly, there are L-NG-nitro arginine methyl ester (L-NAME)- and haloperidol-induced catalepsy as well as the rat acute and chronic models of 'positive-like' schizophrenia symptoms, that BPC 157 counteracted, and resolved the complex relationship of the nitric oxide-system with amphetamine and apomorphine (dopamine agents application), MK-801 (non-competitive antagonist of the N-methyl-D-aspartate receptor) and chronic methamphetamine administration (to induce sensitivity). Thirdly, after rat spinal cord compression, there were advanced healing and functional recovery (counteracted tail paralysis). Likewise, in BPC 157 therapy, there is specific support for each of these topics: counteracted encephalopathies; alleviated vascular occlusion disturbances (stroke); counteracted dopamine disturbances (dopamine receptors blockade, receptors super sensitivity development, or receptor activation, over-release, nigrostriatal damage, vesicles depletion), and nitric oxide-system disturbances ("L-NAME non-responsive, L-arginine responsive," and "L-NAME responsive, L-arginine responsive") (schizophrenia therapy); inflammation reduction, nerve recovery in addition to alleviated hemostasis and vessels function after compression (spinal cord injury therapy). Thus, these disturbances may be all resolved within the same agent's beneficial activity, i.e., the stable gastric pentadecapeptide BPC 157.

The mechanism of attenuation of epithelial-mesenchymal transition by a phosphodiesterase 5 inhibitor via renal klotho expression

Phosphodiesterase-5 (PDE-5) inhibitors induces vasodilation in several organs by blocking cyclic GMP (guanosine monophosphate) degradation. However, the existence of alternative mechanism of action in case of an impaired nitric oxide (NO) system remains controversial. Previous studies suggested that decreased NO bioavailability may result in the downregulation of klotho expression, but the relationship between klotho and NO remains obscure. Therefore, we investigated whether a PDE-5 inhibitor could preserve epithelial-mesenchymal transition (EMT) and relationship exists between the NO and renal klotho expression. Ten-week-old SD rats (N = 24, 200 g, male) were divided (N = 6) into four groups, which received: A LSD, L-NAME 1 mg/mL in drinking water, Udenafil 5 mg/kg subcutaneously and both for 4 weeks. Urine nitrate/nitrite, NGAL (Neutrophil gelatinase-associated lipocalin), and cGMP were measured using ELISA. Kidney was subjected to evaluate PCNA (proliferative cell nuclear antigen), α-SMA (smooth muscle cell antigen), E-cadherin, and klotho expression. Urine cGMP decreased after treatment of PDE-5 inhibitor compared with control due to blocking degradation of cGMP (P < .05, control vs Udenafil and L-NAME with Udenafil groups). Urine NGAL increased after treating of L-NAME and attenuated after using PDE-5 inhibitor (P < .05, control vs L-NAME and L-NAME with Udenafil). PCNA, α-SMA, and E-cadherin (EMT markers) increased after L-NAME treatment and normalized after using PDE-5 inhibitor. Klotho expression showed trend to increase in the L-NAME with PDE-5 inhibitor group compared with the L-NAME group, however, eNOS expression did not change after treatment of L-NAME or PDE-5 inhibitor compared with control. PDE-5 inhibitor alleviates EMT in the kidney via klotho modulation independent of the NO system.