Exercise ameliorates high fat diet induced cardiac dysfunction by increasing interleukin 10.

Increasing evidence suggests that a sedentary lifestyle and a high fat diet (HFD) leads to cardiomyopathy. Moderate exercise ameliorates cardiac dysfunction, however underlying molecular mechanisms are poorly understood. Increased inflammation due to induction of pro-inflammatory cytokine such as tumor necrosis factor-alpha (TNF-α) and attenuation of anti-inflammatory cytokine such as interleukin 10 (IL-10) contributes to cardiac dysfunction in obese and diabetics. We hypothesized that exercise training ameliorates HFD- induced cardiac dysfunction by mitigating obesity and inflammation through upregulation of IL-10 and downregulation of TNF-α. To test this hypothesis, 8 week old, female C57BL/6J mice were fed with HFD and exercised (swimming 1 h/day for 5 days/week for 8 weeks). The four treatment groups: normal diet (ND), HFD, HFD + exercise (HFD + Ex) and ND + Ex were analyzed for mean body weight, blood glucose level, TNF-α, IL-10, cardiac fibrosis by Masson Trichrome, and cardiac dysfunction by echocardiography. Mean body weights were increased in HFD but comparatively less in HFD + Ex. The level of TNF-α was elevated and IL-10 was downregulated in HFD but ameliorated in HFD + Ex. Cardiac fibrosis increased in HFD and was attenuated by exercise in the HFD + Ex group. The percentage ejection fraction and fractional shortening were decreased in HFD but comparatively increased in HFD + Ex. There was no difference between ND and ND + Ex for the above parameters except an increase in IL-10 level following exercise. Based on these results, we conclude that exercise mitigates HFD- induced cardiomyopathy by decreasing obesity, inducing IL-10, and reducing TNF-α in mice

MiR-133a Mimic Alleviates T1DM-Induced Systolic Dysfunction in Akita: An MRI-Based Study

Diabetic cardiomyopathy is a leading cause of heart failure. Developing a novel therapeutic strategy for diabetic cardiomyopathy and characterizing animal models used for diabetes mellitus (DM) are important. Insulin 2 mutant (Ins2+/-) Akita is a spontaneous, genetic, mouse model for T1DM, which is relevant to humans. There are contrasting reports on systolic dysfunction and pathological remodeling (hypertrophy and fibrosis) in Akita heart. Here, we used magnetic resonance imaging (MRI) approach, a gold standard reference for evaluating cardiac function, to measure ejection fraction (indicator of systolic dysfunction) in Akita. Moreover, we performed Wheat Germ Agglutinin (WGA) and hematoxylin and Eosin stainings to determine cardiac hypertrophy, and Masson’s Trichrome and picrosirius red stainings to determine cardiac fibrosis in Akita. MiR-133a, an anti-hypertrophy and anti-fibrosis miRNA, is downregulated in Akita heart. We determined if miR-133a mimic treatment could mitigate systolic dysfunction and remodeling in Akita heart. Our MRI results revealed decreased ejection fraction in Akita as compared to WT and increased ejection fraction in miR-133a mimic-treated Akita. We also found that miR-133a mimic treatment mitigates T1DM-induced cardiac hypertrophy and fibrosis in Akita. We conclude that Akita shows cardiac hypertrophy, fibrosis and systolic dysfunction and miR-133a mimic treatment to Akita could ameliorate them

Genetic basis of hybrid male sterility among three closely related species of <i>Drosophila</i>

455-461The genetic basis of hybrid male sterility among three closely related species, Drosophila bipectillala, D. parabipectinata and D. malerkotliana has been investigated by using backcross analysis methods. The role of Y chromosome, major hybrid sterility (MHS) genes (genetic factors) and cytoplasm (non-genetic factor) have been studied in the hybrids of these three species. In the species pair, bipectinata - parabipectinata, Y chromosome introgression of parabipectinata in the genomic background of bipectinata and the reciprocal Y chromosome introgression were unsuccessful as all males in second backcross generation were sterile. Neither MHS genes nor cytoplasm was found important for sterility. This suggests the involvement of X-Y, X-autosomes or polygenic interactions in hybrid male sterility. In bipectinata - malerkotliana and parabipectinata - malerkotliana species pairs, Y chromosome substitution in reciprocal crosses did not affect male fertility. Backcross analyses also show no involvement of MHS genes or cytoplasm in hybrid male sterility in these two species pairs. Therefore, X- autosome interaction or polygenic interact ion is supposed to be involved in hybrid male sterility in these two species pairs. These findings also provide evidence that even in closely related species, genetic interactions underlying hybrid male sterility may vary

Evaluation of Antiaggressive Activity of Capparis zeylanica Root Extract in Experimental Animal Model

Aggression can ensue due to exposure to an intimidating situation. Aggression is prominently seen when a disturbance occurs in the fine balance of neurotransmitters such as 5-hydroxytryptamine, gamma-aminobutyric acid, dopamine and their receptor subtypes. The present study investigated the ability of 100, 200 and 400 mg/kg of ethanolic extract of Capparis zeylanica root (EECZ) circumvent aggression. Foot shock induced aggression, isolation-induced aggression, resident-intruder aggression and water competition test were utilized as models for screening of antiaggressive activity. Extract was given orally at three different dose levels (100, 200 and 400 mg/kg) once daily for three consecutive days, while Diazepam (2.5 mg/kg), was administered as positive control. EECZ significantly (p&lt;0.05) minimized aggression dose dependently in the entire dose (100, 200, 400 mg/kg). Results suggested that EECZ showed significant antiagressive activity in aforementioned validated models of aggression. EECZ at all dose levels (100, 200 and 400 mg/kg) have shown promising anti-aggressive activity qualitatively comparable to that of diazepam (2.5 mg/kg)

Cardiac matrix: A clue for future therapy

AbstractCardiac muscle is unique because it contracts ceaselessly throughout the life and is highly resistant to fatigue. The marvelous nature of the cardiac muscle is attributed to its matrix that maintains structural and functional integrity and provides ambient micro-environment required for mechanical, cellular and molecular activities in the heart. Cardiac matrix dictates the endothelium myocyte (EM) coupling and contractility of cardiomyocytes. The matrix metalloproteinases (MMPs) and their tissue inhibitor of metalloproteinases (TIMPs) regulate matrix degradation that determines cardiac fibrosis and myocardial performance. We have shown that MMP-9 regulates differential expression of micro RNAs (miRNAs), calcium cycling and contractility of cardiomyocytes. The differential expression of miRNAs is associated with angiogenesis, hypertrophy and fibrosis in the heart. MMP-9, which is involved in the degradation of cardiac matrix and induction of fibrosis, is also implicated in inhibition of survival and differentiation of cardiac stem cells (CSC). Cardiac matrix is distinct because it renders mechanical properties and provides a framework essential for differentiation of cardiac progenitor cells (CPC) into specific lineage. Cardiac matrix regulates myocyte contractility by EM coupling and calcium transients and also directs miRNAs required for precise regulation of continuous and synchronized beating of cardiomyocytes that is indispensible for survival. Alteration in the matrix homeostasis due to induction of MMPs, altered expression of specific miRNAs or impaired signaling for contractility of cardiomyocytes leads to catastrophic effects. This review describes the mechanisms by which cardiac matrix regulates myocardial performance and suggests future directions for the development of treatment strategies in cardiovascular diseases

MiR-133a Mimic Alleviates T1DM-Induced Systolic Dysfunction in Akita: An MRI-Based Study

Diabetic cardiomyopathy is a leading cause of heart failure. Developing a novel therapeutic strategy for diabetic cardiomyopathy and characterizing animal models used for diabetes mellitus (DM) are important. Insulin 2 mutant (Ins2+/-) Akita is a spontaneous, genetic, mouse model for T1DM, which is relevant to humans. There are contrasting reports on systolic dysfunction and pathological remodeling (hypertrophy and fibrosis) in Akita heart. Here, we used magnetic resonance imaging (MRI) approach, a gold standard reference for evaluating cardiac function, to measure ejection fraction (indicator of systolic dysfunction) in Akita. Moreover, we performed Wheat Germ Agglutinin (WGA) and hematoxylin and Eosin stainings to determine cardiac hypertrophy, and Masson’s Trichrome and picrosirius red stainings to determine cardiac fibrosis in Akita. MiR-133a, an anti-hypertrophy and anti-fibrosis miRNA, is downregulated in Akita heart. We determined if miR-133a mimic treatment could mitigate systolic dysfunction and remodeling in Akita heart. Our MRI results revealed decreased ejection fraction in Akita as compared to WT and increased ejection fraction in miR-133a mimic-treated Akita. We also found that miR-133a mimic treatment mitigates T1DM-induced cardiac hypertrophy and fibrosis in Akita. We conclude that Akita shows cardiac hypertrophy, fibrosis and systolic dysfunction and miR-133a mimic treatment to Akita could ameliorate them.</p