Betanin and Peripheral Artery Vasospasm

This article refers to:

Protective Effects of Betanin against Oxidative Stress in a Peripheral Artery Vasospasm Model in Rat

Nowadays, the scientific community has accepted with very little controversy that oxidative stress plays a key role in the onset and development of human diseases. Indeed, an overwhelming amount of scientific publications have shown that this phenomenon is one of the main molecular mechanisms underlying cardiovascular diseases, diabetes, metabolic syndrome, liver diseases, cancer, infections, autoimmune diseases, and several mental illnesses [1]. Oxidative stress is defined as an imbalance between the oxidation of molecules constituting cellular organelles and the antioxidant defenses that the organism has to defend itself against oxidation. An excess of reactive oxygen species produced by either environmental factors or by alterations in cell metabolism oxidizes lipids, proteins, and nucleic acids, leading to cell damage and dysfunction. The most sensitive molecules to oxidative stress are lipids. Lipid peroxidation is a complex chain reaction process due to the oxidation of polyunsaturated fatty acids and other lipids in the endoplasmic membrane or the membranes of the organelles. Some products of lipid peroxidation are highly reactive electrophilic molecules, which alter important cell signaling pathways responsible for disease pathogenesis [2, 3]. One of the consequences of oxidative stress, of great pathophysiological importance, is the stimulation of an inflammatory response. Oxidative stress and inflammation are inextricably linked. Oxidation is associated with inflammation, anti-inflammatory pathways are related to decreased oxidation, increased oxidative stress triggers inflammation, and improvement in redox balance inhibits the inflammatory cellular response [1]. Due to all these considerations, many researchers have devoted enormous efforts to investigate the possible beneficial role of the pharmacological or dietary administration of antioxidants in the evolution of various diseases.

Despite these data, the study of the relationships between oxidative stress and surgical procedures and the possible therapeutic role of antioxidants in the treatment of surgical complications is still an undeveloped field and with a great potential future. For example, data on the relationships between oxidation and the metabolic consequences of surgical stress are scarce. Perisurgical and postsurgical stress is a metabolic response to a state of threatened homeostasis that triggered by factors such as tissue damage, type of anesthesia, hypothermia, hypoxia, dehydration, pain, hemorrhage, and infection [4, 5]. All these factors are potential inducers of oxidative stress or, conversely, can be induced by oxidative stress.

In this article that we are now commenting on, the authors report that the oral administration of betanin has a protective effect against oxidative stress in a peripheral artery vasospasm model in rats [6]. Vasospasm was induced by fixation of a silastic cover around the femoral artery followed by introduction of autologous blood between the cover and the adventitia [7]. Rats that received an oral administration of betanin via orogastric catheterization during 7 days after surgery had bigger arterial lumen diameters and smaller wall thickness than the animals that did not receive betanin, and their values were similar to those of sham-operated, control animals. Moreover, betanin administration was associated with lower serum malondialdehyde and nitric oxide concentrations, both molecules being markers of oxidative stress. Histopathological analysis showed that the femoral arteries of rats that received betanin were similar to those of the control group and did not present the severe morphological alterations in the endothelial layer, the elastic lamina, and the smooth muscle cells that were present in operated rats that did not receive betanin.

Betanin, or beetroot red, is a red glycosidic pigment obtained from many vegetable roots, totally innocuous for human consumption and widely employed in the food industry as a colorant. Betanin is a powerful antioxidant and has attracted attention from researchers due to its anti-inflammatory effects in human hepatic cells. This molecule can induce the translocation of the erythroid 2-related factor 2 antioxidant response element from the cytosol to the nuclear compartment of hepatic cells, enhancing the mRNA and protein expression of antioxidant enzymes, including glutathione S-transferases, NAD(P)H dehydrogenase, and heme oxygenase, and eliciting hepatoprotective and anticarcinogenic effects. The potential pharmacological use of betanin is currently a very promising research field [8]. For example, it would be interesting to investigate the effects of the intravenous administration of betanin in the vasospasm experimental model, since it has been reported that the oral absorption of betanin is lower than 90%, because it is mostly metabolized by the walls of the gastrointestinal tract [9]. It would also be interesting to assess the effects of betanin over time, or depending on whether it is administered through short-term or long-term schedules, and to investigate how long its effect lasts when its administration stops.

Vasospasm is a frequent condition that leads to tissue ischemia and necrosis, and is associated with a high mortality and morbility. This article shows how the administration of betanin prevents and improves the development of this alteration in an experimental model, which highlights its possible therapeutic use in humans. This article is an interesting example of how antioxidant therapy can be useful in reducing stress in a wide range of surgical procedures.

Declaration of Interest

The authors have no competing interests to declare.