The effects of silica on the immune system: An oncologist report

Silica which is one of the most abundant elements in the earth’s crust has numerous industrial applications. From glass and ceramics to foundries and construction industry, diatomaceous earth is used in a multitude of industries. Considering the widespread industrial use of silica, one can assume that millions of individuals working in different industries are exposed to silica and the risks and benefits associated with its exposure.

While in optimal quantities, silica is known to produce a number of positive health effects, such as improved bone mineral density, delayed age-related memory loss, and improved skin elasticity, it is also important to consider that continued exposure to high concentrations of silica can produce several side effects on both mental and physical health of the exposed individual.

In this article, we are particularly discussing the immune system-related effects of silica.

The Immunological Aspects of Silica — What Research Says?

Macrophages are an essential component of the immune system. They are physiological scavengers that rid the body from dead cells and debris. According to this silica review, in addition to this, they are also responsible for phagocytosis — a mechanism through which anything foreign to the body is engulfed and digested by macrophages. Considering these functions of macrophages, we can suggest that their role in critical in defending the human body from any kind of harm caused by a foreign organism or substance.

Silica is known to influence the function of macrophages in both humans and animals. In a study conducted on mice, it was found that silica is toxic for macrophages. The study included administration of injectable silica to mice. Within 3 days of the injection, it was found that silica blocked the innate immune response to sheep erythrocytes (a foreign substance) and caused complex alteration in the spleen cell responsiveness. Overall, silica produced an immune-depressive effect; however, the intensity of effect was different for different preparations of silica.

Another study published in the Journal of Immunotoxicology suggests that silica produces dysregulation of the immune system. The study emphasizes the fact that while silica can produce locally-restricted effects, there is no denying the fact that a possibility for systemic effects exists.

Silica and asbestos both are known to produce respiratory side effects. Inhalation of fine dust containing silica produces a condition called Silicosis, which is characterized by symptoms of cough, shortness of breath, fever, and cyanosis (bluish coloration of membranes due to lack of oxygen).

The study says that silica causes alterations in the function of alveolar macrophages and produces a chain of biological events that may influence the normal respiratory function. These respiratory symptoms can evolve into more serious, systemic immunological effects as well. The findings of the study conclude that silicosis and continued abnormal exposure to silica increases the incidence of autoimmune disorders (conditions in which the immune system considers the healthy cells as foreign bodies and targets them). Apart from autoimmune disorders, silicosis is likely to increase the risk of developing lung cancer as well. This leads us to the assumption that increased exposure to silica reduces the tumor-immunity of the host.

In addition to tumor, exposure to silica can also reduce an individual’s immunity against infectious diseases as well. Exposing experimental animals to silica makes them more susceptible to certain infections caused by different bacteria, viruses, and parasites. In these studies, silica was administered to animals through parenteral route and, therefore, the results may or may not be applicable to the oral preparations of silica.

What makes the finding more complex to comprehend the fact is that reduced phagocytic potential of macrophages is not the only mechanism responsible for reduced immunity. In fact, silica also influences the production of interferons and sensitivity of macrophages to prostaglandins as well, both of which play a major role in the defense mechanism.

A review published in Acta Biomedica suggested that the biological reactions produced inside the body when an individual is exposed to silica are only due to changes in innate immunity, but adaptive immunity as well. The review also suggests that ingestion or exposure to silica results in the death of key immunity cells, macrophages, which produce cytokines to stimulate fibroblasts. The end result of this entire mechanism is the formation of fibro-hyaline tissue and the classical symptoms of silicosis occur.

An interesting conclusion made by the review is that exposure to silica results in silicosis, which in turn is related to several other diseases, such as rheumatoid arthritis, lupus erythematosus, and scleroderma. It’s interesting because on one hand, research advocates the role of silica in joint disorders and age-related bone degeneration, but on the other hand, silica itself increases the risk of an individual of developing rheumatoid arthritis. While rheumatoid arthritis is an auto-immune disease, and osteoporosis and osteoarthritis are not, both of them influence bones and joints, and confusing rheumatoid arthritis for osteoarthritis can lead to serious complications arising from the use of silica as a possible drug for delaying age-related bone degeneration.

Concluding the Findings

After a thorough evaluation of the immunological effects of diatomaceous earth in both animals and humans, one can easily understand the fact that silica depresses the immunity and increases the risk of different health-related disorders, including tumors, respiratory diseases, autoimmune disorders, and infections.

It cannot be concluded whether all forms of silica produce the same effect or silica dust or intravenous silica are only responsible for immunodepression. In addition to this, consensus needs to be built regarding the doses at which silicon toxicity occurs. This is important because silica has shown several positive health effects when used in optimal doses and it can be a useful drug because of its non-toxic nature at low doses. Therefore, more scientific evidence is required in order to determine the risk-benefit ratio for this element that possesses for harmful and beneficial health effects.

Oncologists associate low testosterone levels with obesity, type 2 diabetes mellitus and metabolic syndrom

In a recent announcement, a panel of oncologists made an association between low testosterone in men with diabetes and other health concerns.

Testosterone is an androgen hormone which is produced by the testicles. It happens to be the main male reproductive hormone which promotes and maintains the male reproductive characteristics. However, this hormone is also involved in many other body functions such as strengthening the bones, increasing the muscle mass, and metabolism of fats, proteins, and carbohydrates in the body.

Let’s take a look at the research-based analysis of how low testosterone levels are associated with obesity, decreased fat metabolism, and metabolic syndrome in men.

How Testosterone Works To Promote Fat Metabolism?

Testosterone is a lipid-reducing hormone. It is involved in the inhibition of lipid uptake in the adipose tissues and increases the activity of lipase in the adipocytes which results in increased fat metabolism. Testosterone also increases the process of lipolysis i.e. breakdown of fat, by enhancing the activity and number of beta-adrenergic receptors which are lipolytic in nature. Other than these actions, testosterone is also involved in the inhibition of adipocyte precursor cells differentiation. Due to the inhibition of adipocyte precursor cell differentiation, the number of adipocytes (fat-producing cells)
decreases in the body. This action further decreases the total body fat of a person [1].

How Testosterone Deficiency Can Lead To Obesity And Other Related Medical Conditions?

When the levels of testosterone are decreased in the body, the process of lipolysis becomes slow, which results in decreased fat metabolism. As a result, there’s increased amount of stored fat in the body which can lead to different lipid-associated medical conditions like obesity, hyperlipidemia, and hypercholesterolemia. High levels of LDL i.e. low density lipoprotein (bad cholesterol) is common in all of these conditions which can further lead to other diseases including cardiovascular disorders such as myocardial infarction, hypertension i.e. increased blood pressure, angina, and stroke.

How Is Testosterone Deficiency Associated With Metabolic Syndrome And Type 2 Diabetes Mellitus?

Metabolic syndrome is a cluster of physiological and biochemical abnormalities in the body which are associated with the development of Type 2 Diabetes Mellitus and cardiovascular diseases.

Low levels of testosterone can lead to the development of metabolic syndrome because other than fat metabolism, testosterone is also involved in the breakdown of carbohydrates and protein in the body. There are many testosterone booster supplements on the market that help people maintain healthy levels.

Testosterone works at the molecular level and controls the working of important enzymes which are involved in the major carbohydrate-metabolism processes i.e. glycolysis and glycogen-synthesis cycle. In the process of glycolysis, glucose is broken down by different enzymes which leads to energy generation and formation of pyruvic acid (a non-sugar compound), thereby decreasing the blood glucose levels in the body. In the process of glycogen-synthesis, glucose is converted into its polysaccharide form i.e. glycogen, which happens to be the stored form of glucose in the liver. This process also decreases the blood glucose level in an individual.

Hence, when testosterone levels are decreased in the body, the processes of glycolysis and glycogen-synthesis slow down or become partially inhibited in the body, this leads to an increase in the blood sugar levels which ultimately leads to the development of Type 2 Diabetes Mellitus [2].

Scientific Evidence

A scientific research, published in Diabetes Care medical journal, involved analysis of low testosterone levels association with obesity, metabolic syndrome, and Type 2 Diabetes Mellitus [3].

The epidemiological studies of the result supported a bidirectional relationship of decreased serum testosterone levels with obesity and Type 2 Diabetes Mellitus, which can ultimately lead to the development of metabolic syndrome. It was observed that low testosterone levels in the test subjects caused accumulation of intra-abdominal lipid. Also, when testosterone levels were decreased in men with prostate cancer, for the purpose of initiating the androgen-deprivation therapy, it resulted in an increased body fat mass.

Hence, it was concluded from the study that low testosterone levels are directed associated with obesity, Type 2 Diabetes Mellitus, and metabolic syndrome.

Causes of Low Testosterone Levels in the Body

Age is a natural factor which decreases the amount of testosterone in the body. This decline starts after the age of 30. Some other causes of low testosterone levels include:

  • Infection, injury, or complete loss of testicles
  • Radiation or chemotherapy for cancer treatment
  • Some genetic disorders like Down’s syndrome and Klinefelter’s syndrome
  • Excessive amount of iron in the body i.e. hemochromatosis
  • Malfunctioning of the body’s pituitary gland, which gives the signal for testosterone production to the testicles.
  • Different inflammatory disease like sarcoidosis.
  • Medications used in the treatment of prostate cancer and all corticosteroidal drugs
  • Chronic renal failure or end-stage renal disease
  • Liver cirrhosis and liver enlargement i.e. hepatomegaly
  • Increased anxiety, depression, and stress
  • Smoking and alcoholism

Treatment of Low Testosterone Levels

Testosterone deficiency can be treated via following measures:

  • Intramuscular and subcutaneous injections of testosterone.
  • Use of testosterone gel which is either applied on the skin or inside the nasal cavity.
  • A mucoadhesive material containing testosterone applied above the patient’s teeth twice or thrice a day.

All of these options provide sufficient amount of hormone replacement required by the patient.

Common Adverse Effects of Testosterone Replacement Therapy

When used by healthy individuals, there are no serious adverse effects associated with testosterone replacement therapy. However, some common adverse effects include:

  • Mild fluid retention or edema
  • Oily skin or acne generation
  • Risk of blood clots development
  • Decrease in the size of testicles
  • Mood swings which can lead to aggressive attitude, depression, and anxiety.
  • Increase in the total red blood cell count of the body
  • Decrease in total sperm count

What Can Be Concluded?

In the light of research-based scientific evidence, we can conclude that a person can suffer from different medical conditions which include obesity, Type 2 Diabetes Mellitus, and metabolic syndrome because of low levels of testosterone in their body. Hence, in such cases, adequate measures must be taken to fulfill this deficiency. Also, only a well experienced and registered medical practitioner should be consulted in this regard to ensure optimum efficacy and safety of the treatment.