Hypertension in patients with type-II diabetes: relation to urinary albumin excretion, endothelial function and inflammation

Hepatocyte growth factor exerts beneficial effects on mice with type II diabetes‑induced chronic renal failure via the NF‑κB pathway

Type II diabetes is associated with a low quality of life and inflammation, and is often accompanied by varying degrees of chronic renal failure. Chronic renal failure is considered one of the most important factors that aggravates diabetes and contributes to renal insufficiency in patients with diabetes though cellular fibrosis. It has previously been reported that hepatocyte growth factor (HGF) serves extensive biological roles, and is a multifunctional antifibrotic factor that is involved in kidney development, acute injury and regeneration. The present study aimed to investigate whether HGF exerts beneficial effects on type II diabetes‑induced chronic renal failure in a mouse model. Plasma concentration levels of HGF, tumor necrosis factor (TNF)‑α, monocyte chemoattractant protein (MCP)‑1, interleukin (IL)‑1 and IL‑6 were analyzed prior to and following treatment with HGF. Blood urea nitrogen, plasma creatinine concentrations, and electrolyte, total serum protein, parathyroid hormone and C‑reactive protein levels were analyzed by ELISA. The mechanism underlying the effects of the HGF‑mediated signaling pathway was also investigated in mice with type II diabetes‑induced chronic renal failure. Histological analysis was used to determine the therapeutic effects of HGF on mice with type II diabetes‑induced chronic renal failure. The results indicated that HGF exhibited lower plasma concentrations in mice with type II diabetes‑induced chronic renal failure compared with in healthy mice. In addition, treatment with HGF relieved chronic renal failure via inhibition of inflammation. The results indicated that TNF‑α, MCP‑1 and IL‑1 serum concentration levels were downregulated following treatment with HGF. Conversely, IL‑6 and vascular endothelial growth factor concentration was increased in the HGF‑treated mice compared with in the control mice. The results also demonstrated that HGF treatment downregulated the expression of nuclear factor (NF)‑κB molecules, and target molecules C‑C motif chemokine ligand (Ccl)2, Ccl5, intercellular adhesion molecule 1 and TNF‑α. The present study demonstrated that HGF markedly improved renal failure induced by type II diabetes in a mouse model; histological analyses revealed that renal cell injury was improved following treatment with HGF. In conclusion, these results suggested that HGF may exert beneficial effects on type II diabetes‑induced chronic renal failure via regulation of the NF‑κB signaling pathway.

Resveratrol provides benefits in mice with type II diabetes-induced chronic renal failure through AMPK signaling pathway

Type II diabetes-induced ischemic injuries are known to lead to the rapid degeneration of the kidneys as a result of chronic renal failure. Chronic renal failure is a condition, which typically manifests with symptoms including cardiovascular system and left ventricular hypertrophy, atherosclerosis as well as arterial and aortic stiffness. Resveratrol is a multifunctional compound that has been reported to produce beneficial outcomes for patients with type-II diabetes due to prevention of oxidative stress and apoptosis. However, the beneficial effects of resveratrol in chronic renal failure and the underlying mechanisms have remained to be fully elucidated. The present study investigated the therapeutic effects of resveratrol in mice with chronic renal failure induced by type-II diabetes and assessed the mechanism of action. Oxidative stress, apoptosis and adenosine monophosphate-activated protein kinase (AMPK) in the renal cells of the model mice were assessed. Changes in inflammatory factors renal cells from experimental mice as well as insulin resistance were also analyzed. Morphological changes and immunocytes in renal cells were determined by immunostaining. The results demonstrated that resveratrol treatment decreased the apoptotic rate of renal cells from experimental mice. Oxidative stress also improved in renal cells, as indicated by inhibition of superoxide dismutase and reduced glutathione and 4-hydroxy-2-nonenal levels. In addition, insulin resistance was improved after an 8-week treatment with resveratrol. Inflammatory factors were decreased and factors promoting kidney function were increased after resveratrol treatment. Furthermore, morphological changes were observed to be ameliorated, indicating the therapeutic efficacy of resveratrol. In addition, immunocyte precipitation in renal cells was markedly decreased in resveratrol-treated mice. Importantly, the AMPK signaling pathway was found to be involved in the beneficial effect of resveratrol on the model mice. In conclusion, the present study suggested that resveratrol may be an ideal agent for the treatment of chronic renal failure induced by type-II diabetes through regulation of the AMPK signaling pathway, which should be further investigated in clinical trials.

Plasma Metanephrines Are Associated With Glucose Metabolism in Patients With Essential Hypertension

There is a high incidence of glucose intolerance in essential hypertension. Overactivation of the sympathetic system is one of important causes of essential hypertension. Whether sympathetic system affects glucose metabolism in patients with essential hypertension has never been reported previously. The aim of this study was to explore the association between the sympathetic system activity and glucose metabolism in patients with essential hypertension. A total of 202 essential hypertension inpatients without diabetes were recruited from Shanghai Ruijin Hospital between February 2006 and August 2013. Activity of sympathetic system was quantified by plasma metanephrines (MNs) levels. All subjects received an oral glucose tolerance test. Fasting plasma glucose and 2-hour plasma glucose increased significantly across the quartiles of plasma MNs. The multiple linear regression analysis revealed that plasma MNs were significantly associated with fasting plasma glucose and 2-hour plasma glucose. The area under curve of plasma glucose increased significantly from the lowest plasma MNs quartile across to the highest quartile. The multiple logistic regression analysis revealed that odds ratios (95% confidence interval) for prediabetes in the highest quartile compared with the lowest quartile of plasma MNs was 4.00 (95% confidence interval, 1.16-13.86). Plasma MNs levels are positively associated with plasma glucose in patients with essential hypertension. Patients with high plasma MNs levels had an increased risk of prediabetes.

A common genetic variant of FCN3/CD164L2 is associated with essential hypertension in a Chinese population

Ficolin-3, encoded by FCN3, is the predominant recognition molecule of lectin pathway for the activation of complement component 3 (C3), which is an important risk factor for the development of hypertension. In our previous study, we found the complement system including ficolin-3 was overrepresented in the serum of type 2 diabetic patients. Since type 2 diabetes shares some pathogenic components, including excessive serum C3, with hypertension, this study aims to test the hypothesis that common variants at FCN3 might be associated with essential hypertension in our Chinese population. A total of 1797 subjects were recruited. Of them, 573 were with essential hypertension. Based on HapMap data, three tagging single nucleotide polymorphisms (rs2504778, rs10794501, and rs3813800) in FCN3/CD164L2 region were selected for genotyping by using MassARRAY. Logistic regression analysis was performed to evaluate the genetic effects on the prevalence of hypertension after adjusting for covariates. rs2504778, which locates in the upstream of FCN3 and in the intron of CD164L2, was found to be significantly associated with hypertension after adjusting for covariates (OR = 1.28, 95% CI: 1.05, 1.55, P = .015). Correction for multiple testing did not remarkably attenuate the significance (empirical P = .042 with 10 000 permutations). rs2504778 also showed a nominal association with systolic blood pressure (P = .044) in the quantitative trait analysis. No evidence of correlation with hypertension and blood pressure was observed for rs10794501 and rs3813800. We found that a common variant of FCN3/CD164L2 is associated with hypertension in our Chinese population. More studies with larger sample size are needed to confirm this finding.

Iron behaving badly: inappropriate iron chelation as a major contributor to the aetiology of vascular and other progressive inflammatory and degenerative diseases

BACKGROUND

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular 'reactive oxygen species' (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation.

REVIEW

We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation).The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible.This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, since in some circumstances (especially the presence of poorly liganded iron) molecules that are nominally antioxidants can actually act as pro-oxidants. The reduction of redox stress thus requires suitable levels of both antioxidants and effective iron chelators. Some polyphenolic antioxidants may serve both roles.Understanding the exact speciation and liganding of iron in all its states is thus crucial to separating its various pro- and anti-inflammatory activities. Redox stress, innate immunity and pro- (and some anti-)inflammatory cytokines are linked in particular via signalling pathways involving NF-kappaB and p38, with the oxidative roles of iron here seemingly involved upstream of the IkappaB kinase (IKK) reaction. In a number of cases it is possible to identify mechanisms by which ROSs and poorly liganded iron act synergistically and autocatalytically, leading to 'runaway' reactions that are hard to control unless one tackles multiple sites of action simultaneously. Some molecules such as statins and erythropoietin, not traditionally associated with anti-inflammatory activity, do indeed have 'pleiotropic' anti-inflammatory effects that may be of benefit here.

CONCLUSION

Overall we argue, by synthesising a widely dispersed literature, that the role of poorly liganded iron has been rather underappreciated in the past, and that in combination with peroxide and superoxide its activity underpins the behaviour of a great many physiological processes that degrade over time. Understanding these requires an integrative, systems-level approach that may lead to novel therapeutic targets.