Spirulina algae and vascular function

Cardiovascular diseases are the leading cause of mortality worldwide. These diseases, including ischemic disease, heart failure, and cerebrovascular disease, are highly prevalent in today’s society.

In addition, it is estimated that the impact of these diseases will increase in the coming years due to the aging of the population. Therefore, research focused on describing which mechanisms are altered in these pathologies is absolutely necessary to apply therapeutic strategies, both for possible prevention and treatment.

Aging is considered a physiological process during which notable changes occur in all the systems that make up the body. More specifically, the group led by Dr. Mercedes Ferrer from the Autonomous University of Madrid (UAM) in Spain has spent the last 25 years investigating the mechanisms that regulate vascular tone in different pathophysiological situations, including aging .

In this vital stage, alterations in the production of cellular mediators that regulate vascular function take place in the cardiovascular system. Likewise, there is a decrease in the levels of sex hormones in both sexes, which, in turn, have a negative impact on vascular function.

These negative effects can be summarized as an increase in oxidative stress and vasoconstrictor factors, as well as a decrease in vasodilator factors such as nitric oxide. Modifications in the production of these factors induce changes in the structure of the arterial wall in such a way that they lose elasticity and vascular responses to different stimuli are compromised. All this favors the appearance of cardiovascular pathologies such as high blood pressure, which has a high prevalence in aging.

Mercedes Ferrer’s team has shown that the incubation of arteries from aged animals with an aqueous extract of the microalgae spirulina improves the vascular function of the arteries. The results show the importance that nutritional interventions are gaining in the treatment of cardiovascular pathologies.

In previous studies, the same group demonstrated that a diet supplemented with certain polyunsaturated fatty acids prevented vascular alterations induced by the loss of sex hormones.

Now, these scientists show that another important source of natural compounds with antioxidant and anti-inflammatory properties is spirulina, a microalgae rich in pigments such as chlorophyll and phycocyanin, carotenoids and polyphenols responsible for a high antioxidant capacity described by other researchers.

With this information, Ferrer and his colleagues set out to analyze the effect of an aqueous extract on vascular function in aorta from aged rats, describing some of the mechanisms involved.

“After 3 hours of incubation with the aqueous extract of spirulina, an increase in the vasodilator response was observed due to a greater release and function of vasodilator factors such as nitric oxide and carbon monoxide”, the researchers explain.

Images obtained by confocal microscopy showing the production of superoxide anion (using a visible red fluorescent probe, HE) and the presence of nuclei (using a visible blue fluorescent probe, DAPI) in control aortic segments (in the absence of spirulina) and incubated with spirulina. (Images: UAM)

“The reduction of pro-oxidant mediators – add the authors of the study – was also involved in this effect and, possibly, also in the improvement of contractile responses”.

The results were complemented with analyzes to characterize the composition of the extract, carried out by the group of Dr. Cristina Otero at the Institute of Catalysis and Petrochemicals of the Higher Council for Scientific Research (CSIC) in Spain.

These analyzes show a high antioxidant capacity of the extract, a high content of polyphenols and amino acids, as well as the identification of 12 peptides, some of which correspond to protein fragments that bind chlorophyll and phycocyanin and that seem to have antioxidant properties.

The collaboration between the research groups of Mercedes Ferrer and Cristina Otero will make it possible to analyze the mechanisms involved in the possible beneficial effect of different extracts, not only in arteries that present vascular dysfunction, but in the future it is intended to analyze the effect of dietary supplementation with these extracts in the prevention of cardiovascular diseases.

The study is titled “Spirulina extract improves age-induced vascular dysfunction”. And it has been published in the academic journal Pharmaceutical Biology. (Source: UAM)