In this article, we will discuss one of the main components of Contraccine, chloroquine. Chloroquine is one of the best known compounds in the fight against malaria, but it has many other uses. We will look at the history of chloroquine, its traditional uses, how it is used to treat other diseases and its mechanism of action.
The origin and history of chloroquine
Strictly speaking, chloroquine is not a natural substance, but a synthetic compound that is now produced in laboratories. Essentially it is produced through organic chemical processes developed by the pharmaceutical industry.
The original compound from which chloroquine is derived is quinine. It is a natural substance extracted from the bark of the cinchona tree in the high mountain regions of South America. The cinchona bark was used by indigenous peoples in South America long before European colonization. The bark’s medicinal properties were introduced to Europe in the 17th century and it became a critical treatment for malaria worldwide. It has also been used to treat autoimmune diseases such as lupus and rheumatoid arthritis. With advances in synthetic chemistry, researchers have developed a modified compound derived from quinine, chloroquine, which has proven to be more effective in some ways. The natural source of quinine remains the bark of the cinchona tree, which is still used on an industrial scale in the pharmaceutical industry.
The most common applications
The applications of chloroquine are not limited to malaria, but have also been extended to many other diseases, including autoimmune diseases and some other rare conditions. Here are some areas where the use of chloroquine has been successfully studied:
Autoimmune diseases
Chloroquine has long been used to treat certain chronic autoimmune conditions such as rheumatoid arthritis and systemic lupus erythematosus (SLE). In these cases, chloroquine can reduce inflammation and autoimmune reactions. (dos Reis Neto et al., 2020) (Santos-Moreno et al., 2023)
Skin conditions
Chloroquine has also been successfully studied in the treatment of certain skin conditions, such as psoriasis and amyloidosis. Chloroquine may help reduce skin inflammation and slow down the overproduction of skin cells. (C. Y. Ung et al., 2014)
Viral infections
Chloroquine has also been trialed against various viral diseases such as HIV as well as coronaviruses. Chloroquine and its derived molecule hydroxychloroquine have been shown to fight COVID-19, among other diseases, although this is still a rather controversial and divisive topic among doctors and researchers. (Vincent et al., 2005)
Cancer
The potential use of chloroquine in oncology has also been studied, particularly its ability to inhibit tumour cell growth and survival. Chloroquine affects cell metabolism and promotes programmed cell death (apoptosis) in cancer cells. (Monma et al., 2018) (Witusik-Perkowska et al., 2023)
Metabolic syndrome
Some research suggests that chloroquine can influence the outcome of diabetes and other metabolic diseases by reducing inflammation and improving insulin sensitivity. (McGill et al., 2019)
Chronic inflammatory conditions
The effects of chloroquine have also been studied with positive results in the treatment of Crohn’s disease and ulcerative colitis, as reducing inflammation can be crucial in these conditions. (Leonard B. Weinstock)
Mechanism of action
For different conditions chloroquine can work according to different mechanisms of action. In malaria, for example, chloroquine inhibits the binding of the parasite Plasmodium to haemoglobin, which prevents the parasite from growing and multiplying in red blood cells. (Wellems, 1992) The main areas of application of chloroquine are listed below, along with a description of the mechanism of action.
Reducing inflammation
In autoimmune diseases, chloroquine plays an anti-inflammatory role by reducing the communication between cells that leads to inflammatory processes. Chloroquine decreases the production of inflammatory cytokines such as interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α), which play a role in insulin resistance and cancer development. (Richard et al., 2020)
Autophagy modulation
Chloroquine may affect the process of autophagy, which is the breakdown and recycling of the cell’s own structures. Regulation of autophagy may be important in the function of fat cells and in the treatment of insulin resistance. The inhibitory effect of chloroquine on autophagy may contribute to the management of excess lipids and other molecules accumulated in fat cells, thereby improving insulin sensitivity. (Javaid et al., 2022)
Mitochondrial function
Chloroquine may also affect mitochondrial functions, which are central to energy metabolism and insulin sensitivity. The drug may be able to modulate cellular energy production and levels of oxidative stress in cells, all of which may contribute to the management of certain features of metabolic syndrome. (Javaid et al., 2022)
Lipid metabolism
Although less documented, there is some evidence that chloroquine may affect lipid metabolism, which may also be relevant in the context of metabolic syndrome. Some findings suggest that chloroquine may be able to modify the processing and storage of lipids in the liver and adipose tissues. (Seo et al., 2024)
Controversy and smear campaigns
In the case of the chloroquine molecule, it is noticeable that its potential has been severely underestimated and even forgotten in some areas of medicine and pharmacy. This may be due to the fact that chloroquine is an old compound that is no longer patentable and does not generate significant profits for pharmaceutical companies. As a result, research and development is often diverted towards new, patentable and therefore more economically attractive compounds that can be sold at higher profit margins. In addition, there have been cases where research or applications of chloroquine have been negatively portrayed as they posed a threat to more expensive therapies that had been newly introduced to the market. This phenomenon is particularly striking where the effectiveness of chloroquine in treating certain conditions is comparable or even stronger than newer, more expensive alternatives, without significant side effects. Such situations challenge key decision-makers in healthcare as much as ordinary people, as the fundamental aim ought to be to ensure that new research findings are impartially accepted and, as a result, the best possible treatment is provided for all patients.