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Interaction between Calpain 5, Peroxisome proliferator-activated receptor-gamma and Peroxisome proliferator-activated receptor-delta genes: A polygenic approach to obesity
Abstract and Figures
Obesity is a multifactorial disorder, that is, a disease determined by the combined effect of genes and environment. In this context, polygenic approaches are needed.
To investigate the possibility of the existence of a crosstalk between the CALPAIN 10 homologue CALPAIN 5 and nuclear receptors of the peroxisome proliferator-activated receptors family.
Cross-sectional, genetic association study and gene-gene interaction analysis.
The study sample comprise 1953 individuals, 725 obese (defined as body mass index > or = 30) and 1228 non obese subjects.
In the monogenic analysis, only the peroxisome proliferator-activated receptor delta (PPARD) gene was associated with obesity (OR = 1.43 [1.04-1.97], p = 0.027). In addition, we have found a significant interaction between CAPN5 and PPARD genes (p = 0.038) that reduces the risk for obesity in a 55%.
Our results suggest that CAPN5 and PPARD gene products may also interact in vivo.
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... [6] To the date, fourteen calpain isoforms have been identified. Of these, calpains 1, 2, 5, and 10 are known to be involved in several pathological states including Huntington's disease, [7] Alzheimer's disease, [1,8] stroke, [9] obesity, [10] metabolic syndrome, [11] and type-2 diabetes mellitus [12,13] among others. ...
... TRP 298 (25.8%) [2] TRP 106 (8.2%) [1] HIS 262 (6.8%) [1] TRP 288 (20.8%) [1] TRP 106 (11.6%) [1] HIS 262 (5.8%) [1] TRP 288 (8.7%) [1] HIS 74 (8.4%) [1] HIS 151 (7.0%) [1] TRP 286 (19.3%) [1] TRP 286 (18.4%) [1] HIS 238 (20.1%) [1] TRP 74 (10.0%) [1] TRP 166 (9.9%) [1] HIS 238 (21.1%) [1] PHE 240 (5.8%) [1] TRP 265 (10.3%) [1] Good contacts GLN 109 (94.1%) [39] LEU 112 (75.3%) [12] GLY 113 (97.7%) [24] ASP 114 (78.4%) [8] CYS 115 (88.5%) [25] TRP 116 (63.6%) [15] MET 260 (72.5%) [12] GLU 261 (98.5%) [32] GLY 271 (69.9%) [10] TRP 298 (82.3%) [33] LYS 79 (78.9%) [21] GLN 109 (94.6%) [28] GLY 110 (73.7%) [7] ALA 111 (82.4%) [12] LEU 112 (83.8%) [17] GLY 113 (97.0%) [14] ASP 114 (98.1%) [18] CYS 115 (88.2%) [16] TRP 116 (67.0%) [15] MET 260 (95.8%) [19] GLU 261 (98.3%) [29] GLY 271 (75.6%) [10] TRP 298 (84.9%) [36] GLU 300 (64.2%) [11] ALA 101 (86.2%) [19] LEU 102 (84.5%) [19] GLY 103 (79.7%) [13] CYS 105 (90.6%) [12] TRP 106 (60.9%) [24] GLU 251 (94.3%) [28] VAL 259 (73.1%) [9] LYS 260 (71.4%) [5] GLY 261 (94.5%) [17] HIS 262 (97.1%) [18] TRP 288 (93.1%) [45] TRP 288 (74.8%) [7] GLN 99 (60.7%) [12] ASP 104 (88.4%) [15] CYS 105 (97.2%) [28] TRP 106 (83.6%) [32] LEU 238 (61.5%) [12] GLY 239 (78.8%) [23] SER 241 (88.7%) [18] GLY 261 (97.7%) [20] HIS 262 (94.7%) [24] ALA 263 (96.1%) [25] ARG 337 (76.2%) [15] GLU 339 (83.5%) [26] HIS 74 (77.5%) [25] GLN 75 (93.3%) ...
... TRP 298 (25.8%) [2] TRP 106 (8.2%) [1] HIS 262 (6.8%) [1] TRP 288 (20.8%) [1] TRP 106 (11.6%) [1] HIS 262 (5.8%) [1] TRP 288 (8.7%) [1] HIS 74 (8.4%) [1] HIS 151 (7.0%) [1] TRP 286 (19.3%) [1] TRP 286 (18.4%) [1] HIS 238 (20.1%) [1] TRP 74 (10.0%) [1] TRP 166 (9.9%) [1] HIS 238 (21.1%) [1] PHE 240 (5.8%) [1] TRP 265 (10.3%) [1] Good contacts GLN 109 (94.1%) [39] LEU 112 (75.3%) [12] GLY 113 (97.7%) [24] ASP 114 (78.4%) [8] CYS 115 (88.5%) [25] TRP 116 (63.6%) [15] MET 260 (72.5%) [12] GLU 261 (98.5%) [32] GLY 271 (69.9%) [10] TRP 298 (82.3%) [33] LYS 79 (78.9%) [21] GLN 109 (94.6%) [28] GLY 110 (73.7%) [7] ALA 111 (82.4%) [12] LEU 112 (83.8%) [17] GLY 113 (97.0%) [14] ASP 114 (98.1%) [18] CYS 115 (88.2%) [16] TRP 116 (67.0%) [15] MET 260 (95.8%) [19] GLU 261 (98.3%) [29] GLY 271 (75.6%) [10] TRP 298 (84.9%) [36] GLU 300 (64.2%) [11] ALA 101 (86.2%) [19] LEU 102 (84.5%) [19] GLY 103 (79.7%) [13] CYS 105 (90.6%) [12] TRP 106 (60.9%) [24] GLU 251 (94.3%) [28] VAL 259 (73.1%) [9] LYS 260 (71.4%) [5] GLY 261 (94.5%) [17] HIS 262 (97.1%) [18] TRP 288 (93.1%) [45] TRP 288 (74.8%) [7] GLN 99 (60.7%) [12] ASP 104 (88.4%) [15] CYS 105 (97.2%) [28] TRP 106 (83.6%) [32] LEU 238 (61.5%) [12] GLY 239 (78.8%) [23] SER 241 (88.7%) [18] GLY 261 (97.7%) [20] HIS 262 (94.7%) [24] ALA 263 (96.1%) [25] ARG 337 (76.2%) [15] GLU 339 (83.5%) [26] HIS 74 (77.5%) [25] GLN 75 (93.3%) ...
Calpains are cysteine proteases involved in the development of several human chronic illnesses such as neurodegenerative diseases, cardiovascular ailments, diabetes and obesity which constitutes them into possible therapeutic targets. Here, using molecular dynamic simulations and docking, we studied the binding of known inhibitors to representative members of classical and non‐classical calpains. Our aim is to gain better understanding on the inhibition mechanism of calpains and to develop better and more specific inhibitors. Our atomistic models confirmed the importance of calcium ions for the structure of calpains and, as a consequence, their functionality. With these models and their subsequent use in molecular docking, essential structural requirements were identified for the binding of ligands to the calpain catalytic site that provide useful information for the design of new selective calpain inhibitors.
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... On the one hand, there are reports from Korea of a positive correlation between the presence of the major alleles of rs2016520 and rs1053049 in the PPARD gene and of higher body mass index in their carriers [138]. Moreover, analyses of the adjacent polymorphic point in the PPARD gene showed that the G allele at SNP rs2076167 was overrepresented in the obese subgroup [139]. Study conducted in the Polish population showed that carriers of the C allele at rs1053049 and the G allele at rs2267668 had an increased risk of obesity [123]. ...
Genetic components may play an important role in the regulation of nutrient and energy metabolism. In the presence of specific genetic variants, metabolic dysregulation may occur, especially in relation to the processes of digestion, assimilation, and the physiological utilization of nutrients supplied to the body, as well as the regulation of various metabolic pathways and the balance of metabolic changes, which may consequently affect the effectiveness of applied reduction diets and weight loss after training. There are many well-documented studies showing that the presence of certain polymorphic variants in some genes can be associated with specific changes in nutrient and energy metabolism, and consequently, with more or less desirable effects of applied caloric reduction and/or exercise intervention. This systematic review focused on the role of genes encoding peroxisome proliferator-activated receptors (PPARs) and their coactivators in nutrient and energy metabolism. The literature review prepared showed that there is a link between the presence of specific alleles described at different polymorphic points in PPAR genes and various human body characteristics that are crucial for the efficacy of nutritional and/or exercise interventions. Genetic analysis can be a valuable element that complements the work of a dietitian or trainer, allowing for the planning of a personalized diet or training that makes the best use of the innate metabolic characteristics of the person who is the subject of their interventions.
... Previously, CAPN5 gene variants in humans were shown to be associated with diastolic blood pressure and cholesterol levels, suggesting a role in cardiovascular disease and metabolic syndrome (Hohl-Abrahao & Creutzfeldt, 1991). CAPN5 has also been linked to obesity through interaction with peroxisome proliferator-activated receptor delta (Saez et al., 2008). Although the auditory system (similar to symptomatic ADNIV human patients with the p.Arg289Trp mutation) and body weight (a possible role for CAPN5 in metabolic syndrome and obesity) were significantly altered in these KO mice, examination of the eye showed no significant differences in the mice homozygous for the tm1a allele in Capn5 ( Figure 1f; Blake et al., 2017). ...
Small molecule pharmacological inhibition of dominant human genetic disease is a feasible treatment that does not rely on the development of individual, patient‐specific gene therapy vectors. However, the consequences of protein inhibition as a clinical therapeutic are not well‐studied. In advance of human therapeutic trials for CAPN5 vitreoretinopathy, genetic inactivation can be used to infer the effect of protein inhibition in vivo. We created a photoreceptor‐specific knockout mouse for Capn5 and compared the retinal phenotype to both wild‐type and an existing Capn5 knockout mouse model. In humans, CAPN5 loss‐of‐function gene variants were ascertained in large exome databases from 60,706 unrelated subjects without severe disease phenotypes. Ocular examination of the retina of Capn5 knockout mice by histology and electroretinography showed no significant abnormalities. In humans, there were 22 loss‐of‐function CAPN5 variants located throughout the gene and in all major protein domains. Structural modeling of coding variants showed these loss‐of‐function variants were nearby known disease‐causing variants within the proteolytic core and in regions of high homology between human CAPN5 and 150 homologs, yet the loss‐of‐function of CAPN5 was tolerated as opposed to gain‐of‐function disease‐causing variants. These results indicate that localized inhibition of CAPN5 is a viable strategy for hyperactivating disease alleles. This article is protected by copyright. All rights reserved.
... However, based on the genes targeted by the DM regions between HFH and LFH animals, we can derive some hints. For example, calpain 5 (CAPN5), which encodes a cytosolic cysteine protease that acts on signaling-related molecules and is involved in cell differentiation and proliferation [53], was reported to interact with nuclear receptors and thus to impact metabolism [54]. Mutations in the gene sodium leak channel non-selective (NALCN), which is involved in the control of neuronal excitability, can lead to speech impairment and intellectual disability in humans [55,56]. ...
Background:
Domestication of animals leads to large phenotypic alterations within a short evolutionary time-period. Such alterations are caused by genomic variations, yet the prevalence of modified traits is higher than expected if they were caused only by classical genetics and mutations. Epigenetic mechanisms may also be important in driving domesticated phenotypes such as behavior traits. Gene expression can be modulated epigenetically by mechanisms such as DNA methylation, resulting in modifications that are not only variable and susceptible to environmental stimuli, but also sometimes transgenerationally stable. To study such mechanisms in early domestication, we used as model two selected lines of red junglefowl (ancestors of modern chickens) that were bred for either high or low fear of humans over five generations, and investigated differences in hypothalamic DNA methylation between the two populations.
Results:
Twenty-two 1-kb windows were differentially methylated between the two selected lines at p < 0.05 after false discovery rate correction. The annotated functions of the genes within these windows indicated epigenetic regulation of metabolic and signaling pathways, which agrees with the changes in gene expression that were previously reported for the same tissue and animals.
Conclusions:
Our results show that selection for an important domestication-related behavioral trait such as tameness can cause divergent epigenetic patterns within only five generations, and that these changes could have an important role in chicken domestication.
... CAPN5 encodes calpain-5, a member of the calcium-activated cysteine protease family [1,2]. CAPN5 has been associated with autosomal dominant neovascular inflammatory vitreoretinopathy (ADNIV) [3][4][5][6], obesity [7], Huntington's disease [8,9], and polycystic ovary syndrome [10]. CAPN5 has been found to be localized in the cytoplasm and nucleus of photoreceptor cells, neuronal cells in the retina, and also in the central nervous system [11,12]. ...
CAPN5 has been linked to autosomal dominant neovascular inflammatory vitreoretinopathy (ADNIV). Activation of CAPN5 may increase proteolysis and degradation of a wide range of substrates to induce degeneration in the retina and the nerve system. Thus, we developed an inhibitory intracellular single chain variable fragment (scFv) against CAPN5 as a potential way to rescue degeneration in ADNIV disease or in neuronal degeneration. We report that overexpression CAPN5 increases the levels of the auto-inflammatory factors toll like receptor 4 (TLR4), interleukin 1 alpha (IL1alpha), tumor necrosis factor alpha (TNFalpha) and activated caspase 3 in 661W photoreceptor-like cells and SHSY5Y neuronal-like cells. Both C4 and C8 scFvs specifically recognize human/mouse CAPN5 in 661W cells and SHSY5Y cells, moreover, both the C4 and C8 scFvs protected cells from CAPN5-induced apoptosis by reducing the levels of activated caspase 3 and caspase 9. The cellular expression C4 scFv reduced levels of the pro-inflammatory factor IL1-alpha activated caspase 3 in cells after CAPN5 overexpression. We suggest that CAPN5 expression has important functional consequences in auto-inflammatory processes, and apoptosis in photoreceptor like cells and neural-like cells. Importantly, the specific intracellular targeting of antibody fragments blocking activation of CAPN5 act as inhibitors of CAPN5 functions in neural like cells, thus, our data provides a novel potential tool for therapy in CAPN5-mediated ADNIV or neurodegenerative diseases.
... Similar with our study, several studies from other populations reported the lack of association of PPARδ T294C SNP with obesity, 38,47 Met-S and their related clinical variables. 47 Meanwhile, other studies found significant association with obesity, 46,[48][49][50] increased plasma LDL-C, 6,51 and decreased plasma HDL-C. 6,49 When participants with homozygous wild type for all the three SNPs were clustered together to compare with those with at least one mutant allele, no significant differences in the anthropometric and clinical measurements were observed. ...
Objective:
This study aimed to investigate the association of peroxisome proliferator-activated receptor (PPAR) genes PPARα L162V, PPARγ2 C161T and PPARδ T294C single nucleotide polymorphisms (SNPs) with obesity and metabolic syndrome (Met-S) in a multi-ethnic population in Kampar, Malaysia.
Methods:
Socio-demographic data, anthropometric and biochemical measurements (plasma lipid profile, adiponectin and interleukin-6 [IL-6] levels) were taken from 307 participants (124 males; 180 obese; 249 Met-S; 97 Malays, 85 ethnic Chinese, 55 ethnic Indians).
Results:
The overall minor allele frequencies were .08, .22 and .30 for PPAR α L162V, γ C161T, δ T294C, respectively. All SNPs were not associated with obesity, Met-S and obesity with/without Met-S by χ(2) analysis, ethnicity-stratified and logistic regression analyses. Nevertheless, participants with V162 allele of PPARα had significantly higher IL-6, while those with T161 allele of PPARγ2 had significantly lower HOMA-IR.
Conclusions:
All PPAR SNPs were not associated with obesity and Met-S in the suburban population of Kampar, Malaysia, where only PPARα V162 and PPARγ2 T161 alleles were associated with plasma IL-6 and HOMA-IR, respectively.
... Using subcellular proteomics, 50 proteins were identified. Information regarding the numbered spots is presented in Tables I and II ( [19][20][21][22][23][24][25][26][27]. For these spots, the accession number, protein name, molecular mass (kD), theoretical PI, number of peptides, queries matched and sequence coverage for each particular isoform of a protein were reported. ...
The high glucose‑induced activation of protein kinase C‑β2 (PKC‑β2) has an essential role in the pathophysiology of diabetes‑associated vascular disease. In the present study, human umbilical vein endothelial cells (HUVECs) were cultured in high and normal glucose conditions prior to being infected with a recombinant adenovirus to induce the overexpression of PKC‑β2. The activity of PKC‑β2 was also decreased using a selective PKC‑β2 inhibitor. A series of two‑dimensional electrophoresis images detected ~800 spots in the nuclei, and ~600 spots in the cytosol. Following intra‑ and inter‑group cross‑matching, 38 significantly altered spots were identified as high glucose‑induced and PKC‑β2‑associated nuclear proteins. In addition to the observation that the regulation of key proteins involved in the nuclear factor (NF)‑κB signaling cascade occurred in the cytosol, various transcription factors, including peroxisome proliferator‑activated receptor δ (PPAR‑δ), were also altered in the nuclei. A human protein‑protein interaction network of potential connections of PKC‑β2‑associated proteins was constructed in the proteomics investigation using Biological General Repository for Interaction Datasets. The results indicated that PKC‑β2 may be involved in high glucose‑induced glucose and lipid crosstalk by regulating PPAR‑δ. In addition, NF‑κB inhibitor‑interacting Ras‑like protein 1 may be important in the PKC‑β2‑NF‑κB inhibitor‑NF‑κB signaling pathway in HUVECs under high‑glucose conditions.
... Daxx influences transcriptional control by acting as a corepressor to SUMOylated transcription factors that bind to the SIM on Daxx (57, 63). Consistent with the nuclear localization of CAPN5, a previous genetic association and gene-gene interaction analysis suggests interaction between CAPN5 and the nuclear peroxisome proliferator-activated receptor-␦ (64). Calpains have been implicated in the cleavage of nuclear androgen and estrogen receptors, although the specific calpain isoform has not been identified (65)(66)(67)(68). ...
Calpain 5 (CAPN5) is a non-classical member of the calpain family. It lacks the EF hand motif characteristic of classical
calpains but retains catalytic and Ca2+ binding domains, and it contains a unique C-terminal domain. TRA-3, an ortholog of CAPN5, has been shown to be involved in
necrotic cell death in Caenorhabditis elegans. CAPN5 is expressed throughout the CNS, but its expression relative to other calpains and subcellular distribution has not
been investigated previously. Based on relative mRNA levels, Capn5 is the second most highly expressed calpain in the rat CNS, with Capn2 mRNA being the most abundant. Unlike classical calpains, CAPN5 is a non-cytosolic protein localized to the nucleus and extra-nuclear
locations. CAPN5 possesses two nuclear localization signals (NLS): an N-terminal monopartite NLS and a unique bipartite NLS
closer to the C terminus. The C-terminal NLS contains a SUMO-interacting motif that contributes to nuclear localization, and
mutation or deletion of both NLS renders CAPN5 exclusively cytosolic. Dual NLS motifs are common among transcription factors.
Interestingly, CAPN5 is found in punctate domains associated with promyelocytic leukemia (PML) protein within the nucleus.
PML nuclear bodies are implicated in transcriptional regulation, cell differentiation, cellular response to stress, viral
defense, apoptosis, and cell senescence as well as protein sequestration, modification, and degradation. The roles of nuclear
CAPN5 remain to be determined.
The peroxisome proliferator-activated receptors (PPARs) are a group of nuclear receptors that function as transcription factors regulating the expression of genes involved in cellular differentiation, development, metabolism and also tumorigenesis. Three PPAR isotypes (α, β/δ and γ) have been identified, among which PPARβ/δ is the most difficult to functionally examine due to its tissue-specific diversity in cell fate determination, energy metabolism and housekeeping activities. PPARβ/δ acts both in a ligand-dependent and -independent manner. The specific type of regulation, activation or repression, is determined by many factors, among which the type of ligand, the presence/absence of PPARβ/δ-interacting corepressor or coactivator complexes and PPARβ/δ protein post-translational modifications play major roles. Recently, new global approaches to the study of nuclear receptors have made it possible to evaluate their molecular activity in a more systemic fashion, rather than deeply digging into a single pathway/function. This systemic approach is ideally suited for studying PPARβ/δ, due to its ubiquitous expression in various organs and its overlapping and tissue-specific transcriptomic signatures. The aim of the present review is to present in detail the diversity of PPARβ/δ function, focusing on the different information gained at the systemic level, and describing the global and unbiased approaches that combine a systems view with molecular understanding.
Recent reports have shown that peroxisome proliferator-activated receptor delta (PPARD) plays an important role in different vascular processes suggesting that PPARD is a significant modulator of cardiovascular disease. This review will focus on PPARD in relation to cardiovascular risk factors based on cell, animal and human data. Mouse studies suggest that Ppard is an important metabolic modulator that may have implications for cardiovascular disease (CVD). Specific human PPARD gene variants show no clear association with CVD but interactions between variants and lifestyle factors might influence disease risk. During recent years, development of specific and potent PPARD agonists has also made it possible to study the effects of PPARD activation in humans. PPARD agonists seem to exert beneficial effects on dyslipidemia and insulin-resistant syndromes but safety issues have been raised due to the role that PPARD plays in cell proliferation. Thus, large long term outcome as well as detailed safety and tolerability studies are needed to evaluate whether PPARD agonists could be used to treat CVD in humans.
Previously, we have isolated and characterized an enhancer from the 5'-flanking region of the adipocyte P2 (aP2) gene that directs high-level adipocyte-specific gene expression in both cultured cells and transgenic mice. The key regulator of this enhancer is a cell type-restricted nuclear factor termed ARF6. Target sequences for ARF6 in the aP2 enhancer exhibit homology to a direct repeat of hormone response elements (HREs) spaced by one nucleotide; this motif (DR-1) has been demonstrated previously to be the preferred binding site for heterodimers of the retinoid X receptor (RXR) and the peroxisome proliferator-activated receptor (PPAR). We have cloned a novel member of the peroxisome proliferator-activated receptor family designated mPPAR gamma 2, and we demonstrate that a heterodimeric complex of mPPAR gamma 2 and RXR alpha constitute a functional ARF6 complex. Expression of mPPAR gamma 2 is induced very early during the differentiation of several cultured adipocyte cell lines and is strikingly adipose-specific in vivo. mPPAR gamma 2 and RXR alpha form heterodimers on ARF6-binding sites in vitro, and antiserum to RXR alpha specifically inhibits ARF6 activity in adipocyte nuclear extracts. Moreover, forced expression of mPPAR gamma 2 and RXR alpha activates the adipocyte-specific aP2 enhancer in cultured fibroblasts, and this activation is potentiated by peroxisome proliferators, fatty acids, and 9-cis retinoic acid. These results identify mPPAR gamma 2 as the first adipocyte-specific transcription factor and suggest mechanisms whereby fatty acids, peroxisome proliferators, 9-cis retinoic acid, and other lipids may regulate adipocyte gene expression and differentiation.
Medium-chain acyl-CoA dehydrogenase (MCAD) catalyzes a pivotal reaction in mitochondrial fatty acid (FA) beta-oxidation. To examine the potential role of FAs and their metabolites in the regulation of MCAD gene expression, we measured MCAD mRNA levels in animals fed inhibitors of mitochondrial long-chain FA import. Administration of carnitine palmitoyltransferase I inhibitors to mice or rats resulted in tissue-limited increases in steady-state MCAD mRNA levels. HepG2 cell cotransfection experiments with MCAD promoter reporter plasmids demonstrated that this was a transcriptional effect mediated by the peroxisome proliferator-activated receptor (PPAR). The activity mapped to a nuclear receptor response element that functioned in a heterologous promoter context and specifically bound immunoreactive PPAR in rat hepatic nuclear extracts, confirming an in vivo interaction. PPAR-mediated transactions of this promoter and element were also induced by exogenously added FA and fibric acid derivatives. Induction of PPAR transactivation by perturbation of this discrete metabolic step is unusual and indicates that intracellular FA metabolites that accumulate during such inhibition can regulate MCAD expression and are likely candidates for PPAR ligand(s). These results dictate an expanded role for the PPAR in the regulation of FA metabolism.
Objective:
To investigate the role of the Pro12Ala peroxisome proliferator-activated receptor (PPAR) gamma-2 polymorphism in the susceptibility to the insulin resistance syndrome and its metabolic complications in a population-based nationwide multicenter study in Spain.
Design:
464 unrelated adults (45.3% men and 54.7% women) aged between 35 and 64 years were randomly chosen from a nationwide population-based survey of obesity and related conditions including insulin resistance and cardiovascular risk factors.
Methods:
Anthropometric determinations included: body mass index (BMI), waist-to-hip ratio, sagittal abdominal diameter; biochemical determinations included: fasting plasma glucose concentration and concentration 2 h after an oral glucose tolerance test (OGTT), total cholesterol, high and low density lipoprotein-cholesterol, triglycerides, leptin and insulin. Systolic and diastolic blood pressure were also measured. Genotyping of the PPARgamma-2 Pro12Ala polymorphism was determined by polymerase chain reaction and single strand conformation polymorphism analysis.
Results:
The Ala12 allele frequency was higher in obese men than in lean men (0.15 vs 0.08, P=0.03). Men carriers of the Ala12 allele had a higher BMI than non-carriers (38.9% vs 21.3%; adjusted odds ratio 2.36, 95% confidence interval 1.10-5.05, P=0.03). However, despite higher BMI obese men carriers of the Ala12 allele had lower sagittal abdominal diameter than Pro12 homozygotes (24.1+/-3.2 vs 26.3+/-2.5 cm, P=0.01). The Ala12 allele was associated with lower total triglycerides levels in the overall population and it was also associated with lower fasting insulin levels and a higher insulin sensitivity by homeostasis model assessment (HOMA) in women.
Conclusions:
Our results suggest that the Pro12Ala polymorphism of the PPARgamma-2 gene promotes peripheral deposition of adipose tissue and increased insulin sensitivity for a given BMI. The results in women might be due to their different adipose tissue distribution.
Background and objective
We aimed to estimate the prevalence of the Metabolic Syndrome (MS) in rural and urban areas of the Province of Segovia, Spain, according to the ATPIII criteria (National Cholesterol Education Program's Adults Treatment Panel III report) modified
Subjects and method
Cross-sectional design. Randomized and representative sample of 809 individuals (46% males) aged 35-74 years. Residents in urban and rural areas of the Province of Segovia (Spain). Period of study from January 2000 to January 2003.
Results
The age/sex standardized prevalence of the MS was 17%; 15.7% in males and 18.1% in females. No significant differences in MS prevalence between rural and urban areas were found. The most frequent combination of individual components of MS was abdominal obesity, hyperglycemia and arterial hypertension in males and females. MS was associated with age and obesity in an adjusted logistic regression model. In a second model, abdominal obesity was more common in those individuals with a BMI over 30 kg/m2, secondary education level, age over 45 years, and in female residents in rural areas.
Conclusions
The sex/age adjusted prevalence was lower than that reported in other studies using the ATPIII criteria in Spain. Abdominal obesity was the most frequent single component of MS in females whereas it was arterial hypertension in males.
. The protocol used in each survey was in accordance to the recommen- dations of the Spanish Society for the study of Obesity (SEEDO) to estimate the prevalence of obesity in population studies. RESULTS: The prevalence of obesity in Spanish adult population was 14.5% (95% CI, 13.93-15.07%), significantly higher among women 15.75% (95% CI, 14.89-16.61%), than men 13,39% (95% CI, 11.84-14.94%) (χ2 = 12.470; p = 0.000). Prevalence of obesity significantly increased with age in men and women. The highest rates were estimated for the age group older than 55 years, both among males and females, 21.58% (95% CI, 18.68-24.48%) and 33.9% (95% CI, 32.73-35.07%), res- pectively. CONCLUSION: Obesity is a health problem which affects an important proportion of the Spanish adult
Obesity results from the complex interaction of environmental factors that act on a genetic background that determines the susceptibility to obesity. The identification of such obesity susceptibility genes can provide important insights into the mechanism underlying this condition. While candidate gene approaches have not been tremendously successful in identifying relevant genetic contributors to obesity, except PPAR , the advent of genome-wide strategies has recently revealed novel and unexpected genetic factors with strong associations with obesity and/or diabetes, i.e. FTO, TCF7L2, INSIG2, ENPP1, or FASN (reviewed herein), although some of them are not undebated. Considering the function of the encoded proteins, it will now be of interest to investigate the cellular and molecular mechanisms, how these genetic variations affect body weight, energy metabolism and/or obesity-associated morbidity.
Upon apoptosis induction, the proapoptotic protein Bax is translocated from the cytosol to mitochondria, where it promotes release of cytochrome c, a caspase-activating protein. However, the molecular mechanisms by which Bax triggers cytochrome c release are unknown. Here we report that before the initiation of apoptotic execution by etoposide or staurosporin, an active calpain activity cleaves Bax at its N-terminus, generating a potent proapoptotic 18-kDa fragment (Bax/p18). Both the calpain-mediated Bax cleavage activity and the Bax/p18 fragment were found in the mitochondrial membrane-enriched fraction. Cleavage of Bax was followed by release of mitochondrial cytochrome c, activation of caspase-3, cleavage of poly(ADP-ribose) polymerase, and fragmentation of DNA. Unlike the full-length Bax, Bax/p18 did not interact with the antiapoptotic Bcl-2 protein in the mitochondrial fraction of drug-treated cells. Pretreatment with a specific calpain inhibitor calpeptin inhibited etoposide-induced calpain activation, Bax cleavage, cytochrome c release, and caspase-3 activation. In contrast, transfection of a cloned Bax/p18 cDNA into multiple human cancer cell lines targeted Bax/p18 to mitochondria, which was accompanied by release of cytochrome c and induction of caspase-3-mediated apoptosis that was not blocked by overexpression of Bcl-2 protein. Therefore, Bax/p18 has a cytochrome c–releasing activity that promotes cell death independent of Bcl-2. Finally, Bcl-2 overexpression inhibited etoposide-induced calpain activation, Bax cleavage, cytochrome c release, and apoptosis. Our results suggest that the mitochondrial calpain plays an essential role in apoptotic commitment by cleaving Bax and generating the Bax/p18 fragment, which in turn mediates cytochrome c release and initiates the apoptotic execution. J. Cell. Biochem. 80:53–72, 2000. © 2000 Wiley-Liss, Inc.
An approach for real-time DNA sequencing without the need for electrophoresis has been developed. The approach relies on the detection of DNA polymerase activity by an enzymatic luminometric inorganic pyrophosphate (PPi) detection assay (ELIDA) (Nyrén, P. (1987)Anal. Biochem.167, 235–238). The PPiformed in the DNA polymerase reaction is converted to ATP by ATP sulfurylase and the ATP production is continuously monitored by the firefly luciferase. In the sequencing procedure, immobilized single-stranded template was used in a repeated cycle of deoxynucleotide extension. Real-time signals in the ELIDA, proportional to the amount of incorporated nucleotide, were observed when complementary bases were incorporated. An increased signal-to-noise ratio was obtained by substitution of deoxyadenosine α-thiotriphosphate (dATPαS) for the natural deoxyadenosine triphosphate, dATPαS is efficiently used by the DNA polymerase, but is not recognized by the luciferase. As a model, 15 bases of a single-stranded PCR product were sequenced. The possibility for parallel processing of many samples in an automated manner is discussed.
Basic estrogen receptor (ER) molecule (vero-ER) of the cytosol of porcine uterus was purified 1,200-fold after successive chromatographies on phenyl-Sepharose, hydroxylapatite, and DEAE-cellulose, followed by Sephadex G-150 gel filtration. The purified vero-ER was completely free from endogenous protease and ER-binding factor. The action of Ca2+-dependent cysteine proteinase (calpain) on vero-ER was studied by utilizing the purified receptor and calpains from porcine uterus (endogenous calpain), porcine kidney, and human erythrocytes. Proteolysis of vero-ER was followed by monitoring the disappearance of the binding capability of vero-ER with "8S" ER-forming factor. Vero-ER was proteolyzed by both the endogenous and the exogenous calpains in the presence of Ca2+. The calpains did not attack vero-ER in the absence of Ca2+. The results indicated the absolute requirement by calpain for Ca2+ for the limited hydrolysis of vero-ER. Uterine cytosol was shown to contain, in parallel with calpain, a protease which does not require Ca2+ for the limited proteolysis of vero-ER. The strongly hydrophobic domain of vero-ER, recently shown to be indispensable for the nuclear translocation of vero-ER (Murayama, A. & Fukai, F. (1983) FEBS Lett. 158, 255), was preferentially destroyed by both the Ca2+-requiring and -nonrequiring enzymes. It was assumed that calpain might intervene in the estrogen action by diminishing irreversibly the amount of the cytoplasmic ER capable of translocating into the nucleus.
Calpain (Ca2(+)-activated neutral protease, EC 3.4.22.17) has been reported to hydrolyze the estrogen receptor (ER). However, there has been no report available regarding the role of calpain in the growth of breast cancer cells. To investigate the role of calpain in the growth of various breast cancer cell lines, we employed a synthetic peptide, calpeptin, which is a cell permeable specific inhibitor of calpain. Calpeptin inhibited the cell growth of ER positive breast cancer cells, such as MCF-7, T-47D, and ZR-75-1 in a dose dependent manner in the presence of E2. However, the growth of ER negative breast cancer cells, MDA-MB-231, was not inhibited by calpeptin. It is suggested that calpain plays an important role in the growth of ER positive breast cancer cells.