Effect of Pectin on the Expression of Proteins Associated with Mitochondrial Biogenesis and Cell Senescence in HT29-Human Colorectal Adenocarcinoma Cells

Mitochondria dynamic is regulated by different proteins, maintaining a balance between fission and fusion. An imbalance towards mitochondrial fission has been associated with tumor cell proliferation. The aim of this study was to analyze whether pectin modifies the viability of human colon cancer cells and the expression of proteins involved in mitochondrial fusion and fission. The human colon carcinoma cell line HT29 cells was growth in 10% fetal bovine serum in the absence and presence of pectin. Pectin reduced HT29 cell viability in a concentration-dependent manner, reaching a plateau at 150~300 μmol/L pectin. The presence of 200 μmol/L pectin reduced the expression of dynamin-related protein-1 and increased expression of the mitochondrial fusion-associated proteins mitofusin-1 and 2. Expression of cyclin B1, a protein involved in G2/M transition, was found decreased in pectin-incubated HT29 cells. Moreover, expression of p53 protein, the amount of p53 in the nucleous and β-galactosidase activity, which are all biomarkers for cellular senescence, were significantly higher in pectin-incubated HT29 cells than in HT29 cells incubated without pectin. Expression of the protein B-cell lymphoma 2 (Bcl-2) homologous antagonist/killer was increased in response to incubation with pectin. However, incubation with pectin did not affect expression of Bcl-2-associated X protein or Bcl-2, or the caspase-3 activity. Overall, we concluded that pectin reduces the viability of human HT29 colon cancer cells, which is accompanied with a shift in the expression of proteins associated with mitochondrial dynamics towards mitochondrial fusion. Moreover, incubation with pectin favors cellular senescence over apoptosis in HT29 cells.

Site of mitochondrial reactive oxygen species production in skeletal muscle of chronic obstructive pulmonary disease and its relationship with exercise oxidative stress

Exercise triggers skeletal muscle oxidative stress in patients with chronic obstructive pulmonary disease (COPD). The objective of this research was to study the specific sites of reactive oxygen species (ROS) production in mitochondria isolated from skeletal muscle of patients with COPD and its relationship with local oxidative stress induced by exercise. Vastus lateralis biopsies were obtained in 16 patients with COPD (66 ± 10 yr; FEV(1), 54 ± 12% ref) and in 14 control subjects with normal lung function who required surgery because of lung cancer (65 ± 7 yr; FEV(1), 91 ± 14% ref) at rest and after exercise. In these biopsies we isolated mitochondria and mitochondrial membrane fragments and determined in vitro mitochondrial oxygen consumption (Mit$$\stackrel{.}{\hbox{ V }}$$o(2)) and ROS production before and after inhibition of complex I (rotenone), complex II (stigmatellin), and complex III (antimycin-A). We related the in vitro ROS production during state 3 respiration), which mostly corresponds to the mitochondria respiratory state during exercise, with skeletal muscle oxidative stress after exercise, as measured by thiobarbituric acid reactive substances.State 3 Mit$$\stackrel{.}{\hbox{ V }}$$o(2) was similar in patients with COPD and control subjects (191 ± 27 versus 229 ± 46 nmol/min/mg; P = 0.058), whereas H(2)O(2) production was higher in the former (147 ± 39 versus 51 ± 8 pmol/mg/h; P < 0.001). The addition of complexI, II, and III inhibitors identify complex III as the main site of H(2)O(2) release by mitochondria in patients with COPD and in control subjects. The mitochondrial production of H(2)O(2) in state 3 respiration was related (r = 0.69; P < 0.001) to postexercise muscle thiobarbituric acid reactive substance levels. Our results show that complex III is the main site of the enhanced mitochondrial H(2)O(2) production that occurs in skeletal muscle of patients with COPD, and the latter appears to contribute to muscle oxidative damage.

Insulin receptor substrate-1 expression is increased in circulating leukocytes of patients with acute coronary syndrome

The mechanisms underlying the increased risk of cardiovascular disease associated with diabetes mellitus (DM) are not fully defined. Insulin resistance in human metabolic syndrome patients is associated with decreased expression of the insulin receptor substrate-2- (Irs2-) AKT2 axis in mononuclear leukocytes (MLs). Moreover, acute coronary syndrome (ACS) has been linked through genome-wide association studies to the 2q36-q37.3 locus, which contains the Irs1 gene. Here, we investigated the expression of insulin-signaling pathway genes in MLs from patients with DM, ACS, and ACS plus DM. Quantitative real-time PCR expression studies showed no differences in the mRNA levels of Irs2, Akt2, and Akt1 among all patients. However, Irs1 mRNA expression was significantly increased in patients with ACS—diabetics and nondiabetics—compared with diabetic patients without ACS (P < .02 and P < .005, resp.). The present study reveals for the first time an association between increased Irs1 mRNA levels in MLs of patients with ACS which is not related to DM.

[European Guidelines on Cardiovascular Disease Prevention in Clinical Practice. Spanish adaptation of the CEIPC 2008]

We present the Spanish adaptation made by the CEIPC of the European Guidelines on Cardiovascular Disease Prevention (CVD) in Clinical Practice 2008. This guide recommends the SCORE model for risk evaluation. The aim is to prevent premature mortality and morbidity due to CVD through the management of its related risk factors in clinical practice. The guide focuses on primary prevention and emphasizes the role of the nurses and primary care medical doctors in promoting a healthy life style, based on increasing physical activity, change dietary habits, and non smoking. The therapeutic goal is to achieve a Blood Pressure < 140/90 mmHg, but among patients with diabetes, chronic kidney disease, or definite CVD, the objective is <130/80 mmHg. Serum cholesterol should be < 200 mg/dl and cLDL<130 mg/dl, although among patients with CVD or diabetes, the objective is <100 mg/dl (80 mg/dl if feasible in very high-risk patients). Patients with type 2 diabetes and those with metabolic syndrome must lose weight and increase their physical activity, and drugs must be administered whenever applicable, to reach body mass index (BMI) guided and waist circumference objectives. In diabetic type 2 patients, the objective is glycated haemoglobin <7%. Allowing people to know the guides and developing implementation programs, identifying barriers and seeking solutions for them, are priorities for the CEIPC in order to transfer the recommendations established into the daily clinical practice.

[European Guidelines on Cardiovascular Disease Prevention in Clinical Practice. CEIPC 2008 Spanish adaptation]

The present CEIPC Spanish adaptation of the European Guidelines on Cardiovascular Disease Prevention in Clinical Practice 2008. This guide recommends the SCORE model for risk evaluation. The aim is to prevent premature mortality and morbidity due to CVD by means of dealing with its related risk factors in clinical practice. The guide focuses on primary prevention and emphasizes the role of the nurses and primary care doctors in promoting a healthy life style, based on increasing physical activity, changing dietary habits, and not smoking. The therapeutic goal is to achieve a Blood Pressure < 140/90 mmHg, but in patients with diabetes, chronic kidney disease, or definite CVD, the objective is < 130/80 mmHg. Serum cholesterol should be < 200 mg/dl and cLDL < 130 mg/dl, although in patients with CVD or diabetes, the objective is < 100 mg/dl (80 mg/dl if feasible in very high-risk patients). Patients with type 2 diabetes and those with metabolic syndrome must lose weight and increase their physical activity, and drugs must be administered whenever applicable, with the objective guided by body mass index and waist circumference. In diabetic type 2 patients, the objective is glycated haemoglobin < 7%. Allowing people to know the guides and developing implementation programs, identifying barriers and seeking solutions for them, are priorities for the CEIPC in order to put the recommendations into practice.

[Lipoprotein profile in children and adolescents of the Autonomous Community of Madrid]

BACKGROUND

The aim of study was to know the lipoproteins distribution in children and adolescents from the Autonomous Community of Madrid, Spain, and to compare with other studies.

MATERIAL AND METHODS

The sample included 3,635 children and adolescents (1,853 males and 1,782 females), 4 to 18 years of age. We measured total cholesterol and triglyceride levels with enzymatic methods, the HDL-cholesterol concentration in the supernatant after precipitation of the rest of the lipoproteins, and LDL-cholesterol concentrations were calculated by Friedewald formula.

RESULTS

Total cholesterol levels were 174 +/- 25 mg/dl (4.50 +/- 0.64 mmol/l), triglycerides 60 +/- 24 mg/dl (0.67 +/- 0.28 mmol/l), LDL-cholesterol 100 +/- 22 mg/dl (2.59 +/- 0.58 mmol/l), HDL-cholesterol 61 +/- 13 mg/dl (1.6 +/- 0.34 mmol/l). 19.23% of the children studied had cholesterol levels above 200 mg/dl (> 5.18 mmol/l), and 41.5% of them had levels higher than 180 mg/dl (> 4.66 mmol/l).

CONCLUSIONS

The cholesterol levels as well as the HDL-cholesterol levels in the student population of Madrid, Spain, were higher when compared to other studies. Less variation was found in the LDL-cholesterol concentrations.

[Moderate hypercholesterolemia in children. An index of familial pathology?]

Out of 44 children (with 200 mg/dl cholesterol) 22, with constantly high levels of cholesterol were studied. All belong to a children population from Madrid which 95 percentile for cholesterol was 204 mg/dl. Fifty nine subjects, first degree relatives of these 22 children (17 families) plus probands were studied to determine if moderately elevated cholesterol levels during infancy are related to any form of familial lipidic disorder. Serum lipidic levels, anthropometric measurements, dietary habits a history of atherosclerotic cardiovascular disease (ACVD), were evaluated in all these 81 individuals. Hypercholesterolemia was encountered in 13 of the 59 non probands and high triglyceride levels in 6 people. More than one member of the family was to have some form of lipidic disorder in 12 of 17 families (71%) and in 10 the metabolic abnormality was of a type associated with a higher risk to suffer ACVD. Five families had a combined hyperlipidemia of the multiple lipoproteinemic (4 familiar heterozygotic hypercholesterolemia and one hyperlipidemia with a double phenotype II B and V). All family members were apparently healthy and had no knowledge of their underlying lipidic abnormality. In this group of families antecedents of morbi-mortality because of atherosclerosis were more frequent that in group control families. Authors conclude that a moderately elevated serum cholesterol level during infancy may be a marker for various familiar lipidic disorders. Detection in infantile population of serum cholesterol levels 200 mg/dl should prompt us to perform a more complete lipidic evaluation both in children as well as in their families.