Continuing from the previous blog, I will continue discussing the impacts Li has (Nciri et al., 2011). 

As exposure to Li decreased chemical and biological functions, particularly in the kidneys and liver, there will be an increase in the risk of diseases (Nciri et al., 2011). Given the similar physiology, organs and body plans, rats often suffer similar diseases as humans (Glass, 2016). Therefore understanding the possible diseases rats can suffer from due to exposure to Li is very beneficial to have a grasp of the possible diseases humans might suffer from when exposed to Li pollution for extended periods. 

Figure 1: (American Kidney Fund, 2021)

Diseases that may arise include

1. Chronic kidney disease (CKD)

The probability of developing chronic kidney disease increases exponentially due to damage to renal tissue which is caused by prolonged oxidative stress as mentioned in the previous blog (HealthMatters.io, n.d.; American Kidney Fund, 2021). 

CKD reduces the production of the hormone erythropoietin in the kidneys (Laminate Medical, 2017). Hormone erythropoietin is essential to the body as it protects and stimulates the production of red blood cells (Schoener & Borger, 2022). Hence, CKD, especially in people in the last stage of the disease, often results in anemia which can lead to tiredness, dizziness and dyspnea (shortness of breath) (Laminate Medical, 2017). Left untreated, anemia can lead to organ and heart failure (Laminate Medical, 2017). 

2. Cardiovascular diseases 

Besides anemia, CKD often leads to cardiovascular diseases (Pellegrino et al., 2019). A weaker kidney will put more stress on the heart as more energy is needed to bring blood to the kidney (Centers for Disease Control and Prevention, 2022). Additionally, CKD can alter the blood pressure of patients which will lead to heart disease (Centers for Disease Control and Prevention, 2022). 

CKD can also result in the build-up of salt and fluid which will damage blood vessels and cause atherosclerosis (building up of substances along artery walls) (Laminate Medical, 2017; Mayo Clinic, n.d.). 

The build-up of urea in the body, mentioned in the previous blog, results in toxic reactions and causes inflammation of the pericardium, an important sac around the heart that protects and surrounds the heart (Laminate Medical, 2017; Cleveland Clinic, 2022).

3. Cancer

CKD at the later stages often leads to kidney cancer (National Kidney Foundation, n.d.). National Kidney Foundation (n.d.), observed that people who suffer from end-stage CKD are around 5 times as likely to get kidney cancer compared to people with a healthy kidney. 

Kidney cancer occurs when kidney cell mutates and multiply forming a tumour (Mayo Clinic, 2021). Without prompt treatment, the cancer cell can spread to other parts of the body and may lead to other cancer such as Thyroid cancer and Prostate cancer (American Cancer Society, 2020). 

4. Parkinson’s disease and Alzheimer’s disease 

Li pollution leading to CKD can result in Parkinson’s disease among patients (Nciri et al., 2011). Apart from cardiovascular diseases, CKD can result lead to neurological complications (Meléndez-Flores & Estrada-Bellmann, 2020). Meléndez-Flores & Estrada-Bellmann (2020) suggest that the decrease in cognitive functions will result in Parkinson’s disease which can eventually lead to dementia, Alzheimer’s disease and other neural disorders (Nciri et al., 2011; Meléndez-Flores & Estrada-Bellmann, 2020).

 

As the experiment on lab rats only lasted for a month, further impacts of prolonged exposure to Li are not studied. Should Li pollution become significant in water bodies and food chains in the near future, exposure to Li will stay for a much longer period of time if no active measures are taken to reduce concentrations of Li in the environment. Other parts besides the Kidney and Liver may likely be significantly impacted as the length of exposure increases, leading to a range of other diseases. Additionally, Li at concentrations above 2 g/kg of food was not analysed and hence other possible impacts the higher concentration of Li has on animals and humans have yet to be discovered (Nciri et al., 2011). 

 

Reference List: 

American Cancer Society. (2020, June 9). Living as a Kidney Cancer Survivor. https://www.cancer.org/cancer/kidney-cancer/after-treatment/follow-up.html 

American Kidney Fund. (2021, November 6). Chronic kidney disease (CKD). https://www.kidneyfund.org/all-about-kidneys/chronic-kidney-disease-ckd 

Centers for Disease Control and Prevention. (2022, July 12). Link Between Chronic Kidney Disease, Diabetes, and Heart Disease. https://www.cdc.gov/kidneydisease/publications-resources/link-between-ckd-diabetes-heart-disease.html 

Cleveland Clinic. (2022, July 19). Pericardium: Function and Anatomy. https://my.clevelandclinic.org/health/body/23561-pericardium 

Erythropoietin | You and Your Hormones from the Society for Endocrinology. (n.d.). https://www.yourhormones.info/hormones/erythropoietin/ 

Glass, D. (2016, July 22). How Humans Are Like Rats. A Moment of Science – Indiana Public Media. https://indianapublicmedia.org/amomentofscience/how-humans-are-like-rats.php 

HealthMatters.io. (n.d.). Lipid Peroxides (Genova) | Healthmatters.io. https://healthmatters.io/understand-blood-test-results/lipid-peroxides-genova 

Laminate Medical. (2017, January 11). Effects of Kidney Failure on Body Systems | Laminate Medical. Laminate Medical Technologies. http://www.laminatemedical.com/2017/01/11/effects-kidney-failure-body-systems/ 

Mayo Clinic. (n.d.). Arteriosclerosis / atherosclerosis – Symptoms and causes. https://www.mayoclinic.org/diseases-conditions/arteriosclerosis-atherosclerosis/symptoms-causes/syc-20350569 

Mayo Clinic. (2021, March 15). Kidney cancer – Symptoms and causes. https://www.mayoclinic.org/diseases-conditions/kidney-cancer/symptoms-causes/syc-20352664 

Meléndez-Flores, J. D., & Estrada-Bellmann, I. (2020). Linking chronic kidney disease and Parkinson’s disease: a literature review. Metabolic Brain Disease, 36(1), 1–12. https://doi.org/10.1007/s11011-020-00623-1 

National Kidney Foundation. (n.d.). Kidney Cancer. https://www.kidney.org/atoz/content/kidney-cancer 

Nciri, R., Allagui, M. S., Bourogaa, E., Saoudi, M., Murat, J. C., Croute, F., & Elfeki, A. (2011). Lipid peroxidation, antioxidant activities and stress protein (HSP72/73, GRP94) expression in kidney and liver of rats under lithium treatment. Journal of Physiology and Biochemistry, 68(1), 11–18. https://doi.org/10.1007/s13105-011-0113-3 

Pellegrino, D., La Russa, D., & Marrone, A. (2019). Oxidative Imbalance and Kidney Damage: New Study Perspectives from Animal Models to Hospitalized Patients. Antioxidants, 8(12), 594. https://doi.org/10.3390/antiox8120594 

Schoener, B., & Borger, J. (2022, December 5). NCBI – WWW Error Blocked Diagnostic. https://www.ncbi.nlm.nih.gov/books/NBK536997/