Mèrida, Yucatàn, (May 19, 2021).- In Mexico, the incidence of obesity and overweight, mainly in adolescents aged 12 to 19 years and young adults from the age of 20, increased by about 4%, due to a sedentary lifestyle rooted in the Covid-19 pandemic, said Claudia Ibeth Pérez Díaz, a specialist from the Center for Research and Advanced Studies (Cinvestav).
At the same time, the obesogenic environment with diets high in fat and carbohydrates to which individuals are exposed also influences this trend.
Both factors led to such an increase among adolescents and young people, this was confirmed by the National Health Survey.
She indicated that obesity is a chronic disease with systemic and multifactorial affectations that constitutes a health problem worldwide since studies have shown that this problem triggers associated conditions such as diabetes, hypertension, and cardiovascular problems.
Hence the importance of treating this nutrition problem, since the increase is perceptible both at the national and state levels, therefore, Yucatán is not the exception.
Although there are efforts to counteract this problem, aimed at eating healthier food such as vegetables and fruits, many people have difficulty losing weight, so alternatives such as drug therapy emerge.
To understand the function and usefulness of this type of therapy, Claudia Ibeth Pérez Díaz, a postdoctoral fellow at Cinvestav’s Pharmacology Department, carries out studies on the role of D-norpseudoephedrine (cathine) in the treatment of obesity.
“The idea of using D-norpseudoephedrine, a drug authorized for sale in Mexico, arises because it has not been given importance or such in-depth studies have been done,” she said.
She indicated that cathine is found naturally from the leaves of a shrub called Catha edulis “Khat”, native to the Arabian peninsula.
“This plant has psychostimulant properties, so people in the region tend to chew the leaves to increase energy and, in some individuals, promote satiety,” she stressed.
To conclude that the plant had these properties, through chemical analysis, they found that it has more than 40 metabolites and within them, is cathine.
He mentioned that its chemical structure is very similar to amphetamine, however, D-norpseudoephedrine has a hydroxyl group on the ß-carbon that makes it differentiate, being less addictive and with the power to reduce appetite.
Products based on D-norpseudoephedrine authorized for weight loss can cause side effects such as insomnia and are only prescribed for a maximum period of three months, because afterward, they generate tolerance and their effects are no longer the same as at the beginning.
Pérez Díaz pointed out that “currently, they are working on new combinations of drugs that help to lose weight in the long term.”
The mechanism of action has not yet been clarified, but some studies have demonstrated modulation in some adrenergic receptors and, therefore, the objective of this research was to demonstrate how cathine acts in the central nervous system, mainly in a brain structure called the nucleus accumbens related to food intake.
He added that when this drug was administered in rats, at a systemic level, a reduction in body weight was observed, which was in a dose-dependent manner, that is, at very small amounts the effect was less, but with higher doses, there was greater weight loss.
Another consequence that was detected was the increase in locomotion, the ability to move, and with the administration of stronger doses, another behavior appeared, stereotypy or repetitive movements or postures.
While, at the central nervous system level, this study addressed the structure of the nucleus accumbens and its focus was on the dopaminergic system, he added.
The researcher added that for this, dopamine D1 and D2 receptor antagonists were used which, when administered directly into the nucleus, reversed the effect on weight loss.
Therefore, if D-norpseudoephedrine generated weight loss, when D1R and D2R antagonists acted, the effect caused by D-norpseudoephedrine was reversed, indicating that this modulation was induced by receptors.
Another aspect was that when there was greater locomotion induced by D-norpseudoephedrine, adding these two antagonists also stopped having this psychomotor effect induced by this drug. This demonstrated that the dopaminergic system is involved in the mechanism of action of cathine.
She explained that through electrophysiological recordings in free-moving rats, they found that there was a strong modulation in neuronal activity in the nucleus accumbens, of which 38 percent increased the firing rate after the administration of D-norpseudoephedrine, while 43 percent decreased the rate.
“The study revealed a part of the mechanism of action that was unknown to date,” stated the Cinvestav specialist.
Finally, she announced that the novelty of the research is that D-norpseudoephedrine acts mainly through the D2 receptor, and as a treatment against obesity it can work in the short term; combined with the combination of other drugs could serve for long-term therapy.