Hyperinsulinemia Associated Depression
Haider Sarwar writes in Clinical Medicine Insights (2022) that “Hyperinsulinemia promotes fat accumulation, causing obesity. Being an inflammatory state, obesity can induce further inflammation and is a risk factor for HPA (hypothalamic pituitary axis) dysregulation through hypercortisolism-related hyperglycemia….A disruption on SNS (sympathetic nervous system) activity increases insulin levels, and induces glycogenolysis in the liver and lipolysis in adipose tissue during hypoglycemia. Hyperglycemia-hyperinsulinemia exacerbates inflammation and increases the oxidative stress along with regulating the levels of norepinephrine in the brain sympathetic system. Increased inflammatory cytokines have also been shown to disrupt neurotransmitter metabolism and synaptic plasticity which play a role in the development of depression via inhibiting serotonin, dopamine, melatonin, and glutamate signaling. An increased level of plasma insulin over time in the absence of exercising causes …an increase in insulin resistance due to obesity and further culminates into depression….. Triple therapy with SSRI, bupropion, and cognitive behavioral therapy aids in improving glycemic control, lowering fasting blood glucose, decreasing the chances of relapse, as well as decreasing cortisol levels to improve cognition and the underlying depression.”
Carnitine Reduced Body Weight and Insulin Resistance in Women with PCOS
Carnitine is an amino acid derivative sometimes used as a nutritional supplement. A 2016 study by Mansooreh Samimi and colleagues published in the journal Clinical Endocrinology found that carnitine supplementation reduced weight and insulin resistance in women with polycystic ovary syndrome (PCOS).
In the study, 60 overweight women with PCOS were randomized to receive either 250mg/day carnitine supplements or placebo. After 12 weeks, the carnitine group had lost an average of about 3 kg compared to the placebo group, and centimeters off their waist and hip measurements. Carnitine supplementation also lowered fasting blood glucose, insulin levels in blood, and insulin resistance compared to placebo.