New Trends in the Pharmacological Intervention of PPARs in Obesity: Role of Natural and Synthetic Compounds.

Obesity is a major health concern for a growing fraction of the population, as its prevalence and related metabolic disorders are not fully understood. Over the last decade, many attempts have been undertaken to understand the mechanisms at the basis of this condition, in which the accumulation of fat occurring in adipose tissue leads to the pathogenesis of obesity- related disorders. Among the most recent studies, those on Peroxisome Proliferator Activated Receptors (PPARs) revealed that these nuclear receptor proteins acting as transcription factors, among others, regulate the expression of genes involved in energy, lipid, and glucose metabolisms, and chronic inflammation. The three different isotypes of PPARs, with different tissue expression and ligand binding specificity, exert similar or overlapping functions directly or indirectly linked to obesity. In this study, we reviewed the available scientific reports concerning the PPARs structure and functions, especially in obesity, considering both natural and synthetic ligands and their role in the therapy of obesity and obesity-associated disorders. On the whole, the collected data suggest that there are both natural and synthetic compounds that show beneficial and promising activity as PPAR agonists in chronic diseases related to obesity.

Mephedrone exposure in adolescent rats alters the rewarding effect of morphine in adults.

An increasing number of data show that exposure to mephedrone in adolescence can have long-lasting implication on brain activity and on peripheral organs/tissues. The aim of this study was to investigate whether adolescent exposure to mephedrone (10mg/kg, i.p.) has influence upon the rewarding effect of morphine (5mg/kg, i.p.) in adult rats. Thus, the adolescent rats (on the 30th PND) were treated with mephedrone for 7 consecutive days. When the animals were adult (on the 60th PND) the morphine-induced conditioned place preference (CPP) test was performed. After that, the level of DNA methylation in the striatum was investigated. DNA methylation is one of the epigenetic mechanisms which produces changes in the genome. These alterations may affect the phenotype, without effect on DNA sequences, and has influence on drug addiction. Additionally, in order to check the toxic properties of mephedrone on the peripheral organs, the histopathological examination of kidney and liver was carried out. The present experiments demonstrated that: 1) adolescent mephedrone exposure may intensify the rewarding effect of morphine in adult rats in the CPP test; 2) mephedrone may induce the alterations in DNA methylation in striatum of adult rats leading to changes in gene activity; 3) mephedrone may produce some retrogressive disturbances in kidney and liver, which confirms the toxic properties of this substance.

The antinociceptive effect of 4-substituted derivatives of 5-(4-chlorophenyl)-2-(morpholin-4-ylmethyl)-2,4-dihydro-3H-1,2,4-triazole-3-thione in mice.

The aim of the present experiments was to examine the antinociceptive activity of 4-substituted derivatives of 5-(4-chlorophenyl)-2-(morpholin-4-ylmethyl)-2,4-dihydro-3H-1,2,4-triazole-3-thione in mice. The compounds were synthesized using the so-called Mannich reaction and their structures were confirmed using IR and 1H-NMR spectra. The antinociceptive activity was investigated in two behavioral tests: the hot plate test and the writhing test. For preliminary estimation of other behavioral effects, the locomotor activity of mice, the motor coordination in the rota-rod test, and the myorelaxation in the chimney test were also studied. The changes in body temperature of animals were also recorded. We demonstrated that all examined compounds produced antinociceptive effect, both in the hot plate test and in the writhing test, without impact on the motor coordination and myorelaxation of animals. The pharmacological effect of all drugs has been developed within 60 min after administration of drugs; and in two cases (T-103 and T-104), it has been a short-lasting effect (up to 90 min). Two compounds (T-100 and T-102) also inhibited the locomotor activity of animals. T-104 induced the changes in body temperature of mice. Generally, we demonstrated that combination of two different heterocyclic systems (morpholine and 1,2,4-triazole) might be beneficial for reduction of nociception.