Effects of different diet administration on energy balance, metabolic efficiency and inflammatory state in an animal model

My research project aims to evaluate the possible beneficial effects of Omega (ω)-3 polyunsaturated fatty acids (PUFA) administration in an experimental animal model. I performed the research activity with two different experimental approaches. In the first experimental project, it was used an animal model with obesity-diet induced. Male Wistar rats were fed, for 6 weeks, with three different diets: standard diet (control); HFD enriched with saturated fatty acids (lard); HFD enriched with ω-3 (PUFA) derived from fish oil. In the second experimental project, the rats were fed with standard diet for 4 weeks and two groups received a supplementation with two different milk: the first group were supplemented with low forage milk (LFM), the second group was supplemented with milk low in ω6:ω3 ratio and high conjugated linoleic acid (CLA) levels a high forage milk (HFM). In both experimental projects, at the end of the experimental period was assessed the effects of these dietary treatments on energy balance, lipid metabolism and inflammatory state. Since the skeletal muscle shares with the liver the capacity to influence energy metabolism throughout the body, this work investigated the ability of PUFA to affects lipid metabolism and inflammatory state by modulating the mitochondrial function, ROS emission and Nrf-2 activation in these tissues. Diet supplementation with ω-3 (PUFA) results in a significant decrease in whole body weight, lipid utilization and inflammation with an increased energy expenditure due to the modulation of skeletal muscle and liver mitochondrial efficiency, and to an increased AMPK activation with a consequent reduction of oxidative stress. Moreover, the increased mitochondrial respiration rates were related to an increased mitochondria biogenesis as shown by the increase in PGC1-α and –β expression levels in ω-3 fish oil treated rat models. Furthermore, my data provided the first evidence of HFM beneficial effects on rat metabolism, and suggested that these effects are mediated by the high ω6/ω3 ratio and high content of CLA of HFM

Polyunsaturated Fatty Acids Attenuate Diet Induced Obesity and Insulin Resistance, Modulating Mitochondrial Respiratory Uncoupling in Rat Skeletal Muscle

Omega (ω)-3 polyunsaturated fatty acids (PUFA) are dietary compounds able to attenuate insulin resistance. Anyway, the precise actions of ω-3PUFAs in skeletal muscle are overlooked. We hypothesized that PUFAs, modulating mitochondrial function and efficiency, would ameliorate pro-inflammatory and pro-oxidant signs of nutritionally induced obesity

Modern and Ancestral Genotypes of Mycobacterium tuberculosis from Andhra Pradesh, India

Traditionally, the distribution of the Mycobacterium tuberculosis genotypes in India has been characterized by widespread prevalence of ancestral lineages (TbD1+ strains and variants) in the south and the modern forms (TbD1− CAS and variants) predominating in the north of India. The pattern was, however, not clearly known in the south-central region such as Hyderabad and the rest of the state of Andhra Pradesh where the prevalence of both tuberculosis (TB) and human immunodeficiency virus (HIV) infection is one of the highest in the country; this area has been the hotspot of TB vaccine trials. Spoligotyping of 101 clinical isolates obtained from Hyderabad and rural Andhra Pradesh confirmed the occurrence of major genogroups such as the ancestral (or the TbD1+ type or the East African Indian (EAI) type), the Central Asian (CAS) or Delhi type and the Beijing lineage in Andhra Pradesh. Sixty five different spoligotype patterns were observed for the isolates included in this study; these were further analyzed based on specific genetic signatures/mutations. It was found that the major genogroups, CAS and “ancestral,” were almost equally prevalent in our collection but followed a north-south compartmentalization as was also reported previously. However, we observed a significant presence of MANU lineage in south Andhra Pradesh, which was earlier reported to be overwhelmingly present in Mumbai. This study portrays genotypic diversity of M. tuberculosis from the Indian state of Andhra Pradesh and provides a much needed snapshot of the strain diversity that will be helpful in devising effective TB control programs in this part of the world

Diet Composition.

<p>Diet Composition.</p

Effect of ω-3 PUFA on glucose and lipid metabolism.

<p>HOMA-IR index (A); Plasma insulin (B), and glucose (C) concentrations at different time intervals after glucose load and respective area under curve (AUC) (upper inserts) and insulin tolerance test (D) are shown. Representative western blots of insulin-induced Akt phosphorylation (Ser473) (E), and lipid content (F)in skeletal muscle are also reported. The graphic reported in panel 1E represent the densitometric analysis of protein band obtained in three separate experiments. Haematoxylin-eosin sections of glycogen (G upper panels), ADRP expression (G lower panels) are shown. PAS positive material was stained magenta at a magnification of 20x. Values are expressed as means±SEM from n = 8 animals/group. Different superscripted letters indicate statistically significant differences (P<0.05).</p

Effect of ω-3 PUFA on mitochondrial functions and energy efficiency.

<p>IMF and SS mitochondrial respiration in the presence of succinate (A) or palmitoyl-carnitine (B) as substrates were determined. CPT activity (C); basal (D) or palmitate-induced (E) proton leakage in SS mitochondria and respiration rates at 160 mV (the highest membrane potential common to all the curves) (upper insert); aconitase activity (F); H₂O₂ yield (G), relative mRNA expression of FGF21 (H), PGC1α (I), PGC1β (L) are also shown. Values are expressed as means±SEM from n = 8 animals/group. Different superscripted letters indicate statistically significant differences (P<0.05).</p

Blood Parameters.

<p>Blood Parameters.</p

Genetic affinities within the <i>M. tuberculosis</i> isolates based on spoligotyping.

<p>Different clades corresponding to prevalent genotypes are prominently highlighted. In the inset is the distance coding convention relevant to the genetic relatedness of different isolates within a clade.</p

Details of the <i>M. tuberculosis</i> isolates studied herein.

<p>Details of the <i>M. tuberculosis</i> isolates studied herein.</p