by In a recent study published in Nature’s Signal Transduction and Targeted Therapythe scientists reviewed the therapeutic potential and molecular mechanisms by which dietary interventions influence a wide range of human diseases, such as cardiovascular disease, autoimmune, neurodegenerative and metabolic diseases, as well as cancer.
Study: Effects of dietary intervention on human disease: molecular mechanisms and therapeutic potential. Image Credit: udra11/Shutterstock.com
Background
Diet and nutrition play a fundamental role in human health, and the quantity, composition and quality of diet, as well as meal times, are important determinants of nutrient availability, which in turn regulate physiological processes.
Recent research has also focused on understanding how diet affects disease pathways. However, there is still a paucity of information regarding the impact of specific dietary components on disease prevention or risk.
Results from various epidemiological studies have found that specific dietary patterns modulate the risk of various diseases, including cancer.
While diets rich in sugars and saturated fats have been found to increase the risk of diabetes and cardiovascular disease, those composed mainly of vegetables, fruit and fiber are believed to lower the risk of metabolic diseases and cardiovascular.
Similarly, diets high in processed meat and alcohol are thought to increase the risk of cancer, whereas the Mediterranean diet is believed to reduce the risk of carcinogenesis.
Tumor metabolic pathways and nutrient availability
The researchers reviewed the existing knowledge on the differences in nutrient requirements and metabolic pathways between the tumor microenvironment and the surrounding healthy tissues.
The immune environment inside tumors is a result of the cancer cells depriving the immune cells of essential metabolites such as oxygen and glucose and increasing the levels of adenosine, lactase, and other mediators that further reduce immune cell function.
The metabolic reprogramming that occurs within the tumor microenvironment affects different subsets of immune cells.
Major metabolic pathways in immune cells that are believed to be reprogrammed within the tumor microenvironment include the tricarboxylic acid cycle, glycolysis, the pentose phosphate pathway, oxidative phosphorylation, the amino acid pathway, and fatty acid synthesis.
The review examined each of these pathways in terms of changes in nutritional requirements and metabolic characteristics within the tumor microenvironment.
Nutritional interventions and cancer
The impact of dietary interventions on diseases, including cancer, can be better understood with a thorough understanding of the metabolic pathways of macronutrients such as proteins, fats and carbohydrates.
Systemic metabolism can be modulated by controlling macronutrient intake and influencing the metabolic pathways used by these macronutrients.
Special diets such as ketogenic diets, restricted caloric diets, high-fat diets, diets that mimic fasting, and even high-salt diets, as well as dietary restrictions, are based on the concept of systemic metabolism modifications through modifications macronutrient intakes.
The review discussed these different dietary interventions in detail, providing a comprehensive summary of the molecular mechanisms by which specific diets influence clinical outcomes in patients with cancer.
The researchers also reviewed studies that evaluated the role of dietary factors in cancer treatment, particularly the use of nutritional interventions to improve the effectiveness of immunotherapy and other cancer treatments.
Caloric restriction was found to increase the response of T cells to immunotherapy. In contrast, the effectiveness of chemotherapy and immunotherapy has been improved by the use of caloric restriction mimetics.
Caloric restriction has also been found to be effective in modifying the tumor microenvironment when combined with radiotherapy for cases of triple-negative breast cancer.
The review comprehensively analyzed the results of various studies that examined the effectiveness of specific dietary restrictions in combination with various cancer therapies to modify the tumor microenvironment.
The scientists also discussed the changes induced in the gut microbiome by dietary interventions and the effectiveness of gut microbiome changes in combination with cancer therapy.
Studies have found that changes in the diversity and composition of the gut microbiome caused by dietary interventions alter the levels of microbiota-derived metabolites that directly influence antitumor activity.
Nutritional interventions and other diseases
The review also discussed the role of dietary interventions in preventing or delaying, or sometimes even stimulating, the progression of cardiovascular, neurodegenerative, metabolic and autoimmune diseases.
They examined the link between nutrient availability, dietary patterns, and neurodegenerative diseases such as Parkinson’s disease, Alzheimer’s disease, epilepsy, and Huntington’s disease, among others.
The impact of dietary interventions on autoimmune disorders such as systemic lupus erythematosus, Hashimoto’s thyroiditis, inflammatory bowel disease, and multiple sclerosis was also covered in this review.
Conclusion
Overall, the results of this review showed that dietary interventions play a significant role in human health and disease, with some interventions, alone or in combination with other therapies, slowing the progression of diseases such as cancer or improving efficacy treatment methods, and others that increase the risk of various diseases.
