Role of apolipoprotein E in renal damage protection

Relationship between aging and control of metabolic syndrome with telomere shortening: a cross-sectional study

Aging is considered one of the major risk factors for several human disorders. The telomere plays a crucial role in regulating cellular responsiveness to stress and growth stimuli as well as maintaining the integrity of the Deoxyribonucleic Acid (DNA), and aging leads to the progressive decline in the telomere length (TL) due to continuous cell division. The aim of this study was to determine the relationship between TL and advancing age and the impact of metabolic syndrome (MetS) on TL. Firstly, we determined the association of advancing age and TL, by measuring telomere length (T/S ratio) in healthy volunteers (n = 90). The TL was compared between normal population and patients with metabolic syndrome (n = 298). The age matched controlled and uncontrolled MetS patients (n = 149) were also compared for their TL T/S ratio. The TL showed negative correlation with advancing age, whereas the significant change was observed at the cut-offs of 40 and 70 years defining 40 with longer TL and 70 as shorter TL. The longest T/S ratio at 2.46 was measured at the age range of 1 year in healthy volunteers, while elderly population showed considerably shorter TL. The patients older than 60 years with poor or uncontrolled MetS had shorter TL, as compared to the controlled MetS. In conclusion our findings suggest that TL was negatively correlated with advancing age. Uncontrolled metabolic syndrome appeared to have worsening effects on TL. Telomere length appears to have potential to be used a parameter to determine age. However, further large scale studies are recommended to make firm guidelines.

Proteomic research on new urinary biomarkers of renal disease in canine leishmaniosis: Survival and monitoring response to treatment

The objective of our study was to search for survival biomarkers (SB) and treatment response monitoring biomarkers (TRMB) in the urinary proteome of dogs with renal disease secondary to canine leishmaniosis (CanL), using UHPLC-MS/MS. The proteomic data are available via ProteomeXchange with identifier PXD042578. Initially, a group of 12 dogs was evaluated and divided into survivors (SG; n = 6) and nonsurvivors (NSG; n = 6). A total of 972 proteins were obtained from the evaluated samples. Then, bioinformatic analysis reduced them to 6 proteins like potential SB increased in the NSG, specifically, Haemoglobin subunit Alpha 1, Complement Factor I, Complement C5, Fibrinogen beta chain (fragment), Peptidase S1 domain-containing protein, and Fibrinogen gamma chain. Afterwards, SG was used to search for TRMB, studying their urine at 0, 30, and 90 days, and 9 proteins that decreased after treatment were obtained: Apolipoprotein E, Cathepsin B, Cystatin B, Cystatin-C-like, Lysozyme, Monocyte differentiation CD14, Pancreatitis-associated precursor protein, Profilin, and Protein FAM3C. Finally, enrichment analysis provided information about the biological mechanisms in which these proteins are involved. In conclusion, this study provides 15 new candidate urinary biomarkers and an improved understanding of the pathogenesis of kidney disease in CanL.

Gene expression plasticity and desert adaptation in house mice

Understanding how organisms adapt to new environments is a key problem in evolution, yet it remains unclear whether phenotypic plasticity generally facilitates or hinders this process. Here we studied evolved and plastic responses to water-stress in lab-born descendants of wild house mice (Mus musculus domesticus) collected from desert and non-desert environments and measured gene expression and organismal phenotypes under control and water-stressed conditions. After many generations in the lab, desert mice consumed significantly less water than mice from other localities, indicating that this difference has a genetic basis. Under water-stress, desert mice maintained more weight than non-desert mice, and exhibited differences in blood chemistry related to osmoregulatory function. Gene expression in the kidney revealed evolved differences between mice from different environments as well as plastic responses between hydrated and dehydrated mice. Desert mice showed reduced expression plasticity under water-stress compared to non-desert mice. Importantly, non-desert mice under water-stress generally showed shifts toward desert-like expression, consistent with adaptive plasticity. Finally, we identify several co-expression modules linked to phenotypes of interest. These findings provide evidence for local adaptation after a recent invasion and suggest that adaptive plasticity may have facilitated colonization of the desert environment.

Metabolic Syndrome and Neuroprotection

Introduction: Over the years the prevalence of metabolic syndrome (MetS) has drastically increased in developing countries as a major byproduct of industrialization. Many factors, such as the consumption of high-calorie diets and a sedentary lifestyle, bolster the spread of this disorder. Undoubtedly, the massive and still increasing incidence of MetS places this epidemic as an important public health issue. Hereon we revisit another outlook of MetS beyond its classical association with cardiovascular disease (CVD) and Diabetes Mellitus Type 2 (DM2), for MetS also poses a risk factor for the nervous tissue and threatens neuronal function. First, we revise a few essential concepts of MetS pathophysiology. Second, we explore some neuroprotective approaches in MetS pertaining brain hypoxia. The articles chosen for this review range from the years 1989 until 2017; the selection criteria was based on those providing data and exploratory information on MetS as well as those that studied innovative therapeutic approaches.

Pathophysiology: The characteristically impaired metabolic pathways of MetS lead to hyperglycemia, insulin resistance (IR), inflammation, and hypoxia, all closely associated with an overall pro-oxidative status. Oxidative stress is well-known to cause the wreckage of cellular structures and tissue architecture. Alteration of the redox homeostasis and oxidative stress alter the macromolecular array of DNA, lipids, and proteins, in turn disrupting the biochemical pathways necessary for normal cell function.

Neuroprotection: Different neuroprotective strategies are discussed involving lifestyle changes, medication aimed to mitigate MetS cardinal symptoms, and treatments targeted toward reducing oxidative stress. It is well-known that the routine practice of physical exercise, aerobic activity in particular, and a complete and well-balanced nutrition are key factors to prevent MetS. Nevertheless, pharmacological control of MetS as a whole and pertaining hypertension, dyslipidemia, and endothelial injury contribute to neuronal health improvement.

Conclusion: The development of MetS has risen as a risk factor for neurological disorders. The therapeutic strategies include multidisciplinary approaches directed to address different pathological pathways all in concert.

Metabolic syndrome, aging and involvement of oxidative stress

The prevalence of the metabolic syndrome, a cluster of cardiovascular risk factors associated with obesity and insulin resistance, is dramatically increasing in Western and developing countries. This disorder consists of a cluster of metabolic conditions, such as hypertriglyceridemia, hyper-low-density lipoproteins, hypo-high-density lipoproteins, insulin resistance, abnormal glucose tolerance and hypertension, that-in combination with genetic susceptibility and abdominal obesity-are risk factors for type 2 diabetes, vascular inflammation, atherosclerosis, and renal, liver and heart diseases. One of the defects in metabolic syndrome and its associated diseases is excess of reactive oxygen species. Reactive oxygen species generated by mitochondria, or from other sites within or outside the cell, cause damage to mitochondrial components and initiate degradative processes. Such toxic reactions contribute significantly to the aging process. In this article we review current understandings of oxidative stress in metabolic syndrome related disease and its possible contribution to accelerated senescence.

Signaling pathways of apoE and its role of gene expression in glomerulus diseases

The roles of apolipoprotein E (apoE) in regulating plasma lipids and lipoproteins levels have been investigated for over several decades. However, in different tissues/cells, the role of apoE was different, such as that it was a risk factor for cancer, but some reports stated that apoE was a protective factor for renal diseases. At the moment, most of the studies find that apoE not only acts as a ligand for metabolism of lipids, but also plays as a factor to regulate lots of signaling pathways. There was rare review to sum up the signaling pathways for apoE, and there was also rare review to widely review the gene expression of apoE in glomerulus diseases. This review was performed to provide a relatively complete signaling pathways flowchart for apoE to the investigators who were interested in the roles of apoE in the pathogenesis of glomerulus diseases. In the past decades, some studies were also performed to explore the association of apoE gene expression with the risk of glomerulus diseases. However, the role of apoE in the pathogenesis of glomerulus diseases was controversial. Here, the signal transduction pathways of apoE and its role of gene expression in the pathogenesis of glomerulus diseases were reviewed.

Association of apoE gene expression and its gene polymorphism with nephrotic syndrome susceptibility: a meta-analysis of experimental and human studies

Apolipoprotein E (apoE) is a major protein in the lipoprotein transport system that plays a well established role in lipids metabolism. apoE gene contains three potential alleles: ε2, ε3 and ε4, forming six genotypes: ε2ε2, ε2ε3, ε2ε4, ε3ε3, ε3ε3 and ε4ε4. The disorder of lipids metabolism is an important feature for nephrotic syndrome (NS). There were some investigations reporting that apoE and its gene polymorphism was associated with NS susceptibility. However, the mechanism was unclear and the association was still controversial. This meta-analysis was performed to evaluate the association between apoE and NS risk in experimental and human studies. A predefined literature search and selection of eligible relevant studies were performed to collect the data from electronic databases, and eligible investigations were synthesized using meta-analysis method. In experimental models, twelve comparisons were included and a definitely positive association was observed between apoE protein expression and NS susceptibility (WMD = 1.88, P < 0.00001). However, in human, there was only two studies included for meta-analysis and a positive association between apoE protein expression and NS susceptibility wasn't found (OR = 108.10, P = 0.32). Interestingly, ε3ε3, ε3ε4, ε3 and ε4 were associated with NS susceptibility (ε3ε3: OR = 0.56, P = 0.002; ε3ε4: OR = 1.91, P = 0.02; ε3: OR = 0.61, P = 0.001; ε4: OR = 1.85, P = 0.009). In conclusion, the apoE gene expression was associated with the NS susceptibility in experimental studies, and the apoE ε3ε3, ε3ε4, ε3 and ε4 were associated with the onset of NS in human studies. This study supported that the disorder of apoE was one of the possible causes for NS risk. However, more studies should be performed to investigate this relationship in the future.

Recent progress in histochemistry and cell biology

Studies published in Histochemistry and Cell Biology in the year 2011 represent once more a manifest of established and newly sophisticated techniques being exploited to put tissue- and cell type-specific molecules into a functional context. The review is therefore the Histochemistry and Cell Biology's yearly intention to provide interested readers appropriate summaries of investigations touching the areas of tissue biology, developmental biology, the biology of the immune system, stem cell research, the biology of subcellular compartments, in order to put the message of such studies into natural scientific-/human- and also pathological-relevant correlations.