As we round the final corner before fall recess, take a minute to catch your breath with some of this week’s scientific discoveries.
Ketogenic diets in relation to depression and anxiety
In a study published in JAMA Psychiatry, researchers examined the possible associations between ketogenic diets and depressive and anxiety symptoms in adults. Ketogenic diets consist of avoiding carbohydrates and consuming fats to place the body in ketosis, a metabolic state where fat, instead of glucose, is used as an energy source. Originally used as a treatment for epilepsy patients, ketogenic diets have become well-known in popular culture as a method of weight loss. However, the diet has potential risks of cardiovascular issues and may increase the chance of nutrient deficiency.
The recent study suggested ketogenic diets might have a potentially therapeutic effect on the brain and mental illnesses, stating specifically the improvement of mitochondrial metabolism and neurotransmitter function and decreased oxidative inflammation during ketosis. Researchers collected data from studies that included participants that were on a ketogenic diet as well as psychiatric scale data such as Patient Health Questionnaire–9 or the Generalized Anxiety Disorder–7. As stated in the study, this included randomized clinical trials, quasi-experimental studies, cross sectional studies, case series and case reports. After meta-analyses, the study concluded that ketogenic diets eased depressive symptoms to a certain, moderate degree, but not anxiety symptoms.
CRISPR-Cas9 technology to decrease ANGPTL3 protein levels
A study published in The New England Journal of Medicine examined the impact of utilizing CRISPR-Cas9 technology to target gene angiopoietin-like protein 3 (ANGPTL3) in a phase 1 clinical trial. ANGPTL3 encodes a protein that regulates low-density lipoprotein and triglyceride levels through the inhibition of their lipases. Low-density lipoprotein, often categorized as “bad” cholesterol, and high triglycerides have been correlated with arteriosclerosis as well as artery hardening. Decreased expression of ANGPTL3 has been found to be correlated with a decreased risk of atherosclerotic cardiovascular disease. The researchers in the study induced a loss-of-function mutation with the delivery of CRISPR-Cas9 mRNA and guide RNA targeting the liver specifically via lipid nanoparticles.
The participants received the treatment through an intravenous infusion of one of the four doses: 0.1, 0.3, 0.6 and 0.8 mg per kilogram. The strongest dose, 0.8 mg per kilogram, reported a 73.2% decrease in ANGPTL3 protein levels. Researchers stated that some limitations included the small number of participants as well as the varying baseline levels of low-density lipoprotein and triglyceride levels.
Umbilical cord hormones and childhood anthropometric measurements
Umbilical cord blood is the blood that remains in the umbilical cord after birth. A study published in JAMA Pediatrics observed that hormones in the umbilical cord might have a potential association with childhood anthropometric measurements like BMI and waist to height ratio, highlighting this research as a particular area of interest to examine the development of obesity. The hormones measured in this study included glucagon-like-peptide-1, peptide YY, pancreatic polypeptide and leptin. Glucagon-like-peptide-1 is a hormone that regulates blood sugar levels, decreases appetite and promotes a feeling of fullness. Peptide YY is a gut hormone that is released after meals to reduce appetite. Pancreatic polypeptide levels interact with other molecules and proteins in the pancreas in addition to appetite regulation, while leptin has a similar purpose in the adipose tissue.
The study utilized a birth cohort design, first attaining the hormone levels and then following up with the participants four to six years later. The researchers concluded that peptide YY and pancreatic polypeptide levels were associated with “rapid growth” and higher BMI z-scores. This suggests that the risk of obesity may be influenced by factors present at birth and followed into early childhood.