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.”
Cold Water Immersion Can Have Benefits
From:
Medscape Staff, December 08, 2022
“Bathing in cold water or ice may cut “bad” body fat and reduce the risk of disorders such as diabetes, but other claims of health benefits are less defined, according to researchers from the Arctic University of Norway and the University Hospital of North Norway.
WHAT TO KNOW:
- Immersion in cold water has a major impact on the body. It elevates the heart rate and has positive effects on brown adipose tissue, a type of “good” body fat that is activated by cold and may protect against obesity and cardiovascular disease.
- Exposure to cold water or cold air also appears to increase the production of the protein adiponectin by adipose tissue. Adiponectin plays a key role in protecting against insulin resistance, diabetes, and other diseases.
- Repeated cold-water immersions by inexperienced as well as experienced swimmers during the winter months significantly increased insulin sensitivity and decreased insulin concentrations.
- Numerous health and well-being claims from regular exposure to the cold, such as weight loss, better mental health, and increased libido, may be explained by other factors, including an active lifestyle, trained stress handling, social interactions, as well as a positive mindset.
- Those seeking to voluntarily practice cold-water emersion need to be educated about possible health risks associated with taking a dip in icy water, which include the consequences of hypothermia, and of heart and lung problems, which are often related to the shock from the cold.”
Low Levels of Acetyl-L-Carnitine Associated with Insulin Resistance in Traumatized Children
Researcher Carla Nasca and colleagues from the Rockefeller University reported at a late-2018 scientific meeting that depressed patients with a history of childhood adversity had low levels of the amino acid acetyl-L-carnitine and also exhibited insulin resistance. This is noteworthy because in a series of small studies, acetyl-L-carnitine supplements have had antidepressant effects. In laboratory animals, acetyl-L-carnitine also sensitizes insulin receptors. This suggests the possibility that the supplements could provide a two-for-one benefit in depressed patients with a history of adversity in childhood.
Bipolar Disorder and Diabetes Linked
A systematic literature review in 2016 showed a definitive link between bipolar disorder and diabetes. Bipolar disorder almost doubles the risk of diabetes while diabetes more than triples the risk of bipolar disorder. The article by Ellen F. Charles and colleagues was published in the International Journal of Bipolar Disorders.
The review included seven large cohort studies. The studies, based on elderly populations only, examined bipolar disorder and diabetes rates. Charles and colleagues suggested that shared mechanisms could cause both illnesses. New disease models that explain the link between bipolar disorder and diabetes could lead to better treatments.
The review also reported that both bipolar disorder and diabetes were independently associated with risk of cognitive decline and dementia in these elderly individuals. People with diabetes had more brain atrophy on average than others who share their age and gender but did not have diabetes. People with bipolar disorder who also had diabetes and either insulin resistance or glucose intolerance had neurochemical changes in the prefrontal cortex that indicated poor neuronal health. In some cases, these patients also had reduced brain volume in the hippocampus and cortex.
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.
Diabetes May Contribute to Low Hippocampal Volume in Bipolar Disorder
Type 2 diabetes can damage the brain, particularly by reducing volume of the hippocampus, and frequently occurs in patients with bipolar disorder. A recent study of patients with bipolar disorder and abnormal glucose metabolism showed that patients with bipolar disorder who also had insulin resistance, glucose intolerance, or type 2 diabetes had smaller hippocampi than both patients with bipolar disorder and normal glucose function and normal control participants without a psychiatric disorder. In those with bipolar disorder and glucose abnormalities, age was associated with lower hippocampal volume to a greater extent than in bipolar patients with normal glucose function.
In the study, published by Tomas Hajek et al. in the journal Neuropsychopharmacology, not only did diabetes or prediabetes reduce the size of the hippocampus, but also reduced gray matter in the cerebral cortex, including the insula.
The researchers hope that treating diabetes, or possibly even its initial symptoms, more effectively may prevent these gray matter losses and slow brain aging in patients with bipolar disorder.
Metformin Effective for Treating Antipsychotic-Induced Amenorrhea, Weight Gain, and Insulin Resistance in Women
Treatment with antipsychotics often has side effects such as amenorrhea (loss of the menstrual period) and weight gain that make sticking to a treatment regimen difficult for some patients. A 2012 study by Wu et al. in the American Journal of Psychiatry suggests that the drug metformin, often used to treat diabetes, can reverse these changes. The 84 female patients recruited for the study were being treated for a first episode schizophrenia, were on one antipsychotic, and had experienced amenorrhea for several months. They received either placebo or 1000mg/day of metformin in addition to their antipsychotic treatment for six months. Seventy-six women completed the trial.
Metformin was able to reverse the side effects in many of the women. Menstruation returned in 28 of the patients taking metformin compared to only two patients taking placebo. Among those on metformin, body mass index (BMI) decreased by a mean of 0.93, compared to a mean increase in those on placebo (0.85). Insulin resistance improved in the women on metformin as well.
Editor’s Note: Metformin can also delay the onset of type II diabetes in those in the borderline diabetic range. The weight loss on metformin was not spectacular and other options include the combination of the antidepressant bupropion (Wellbutrin) and the opiate antagonist naltrexone (Revia, 50mg/day), monotherapy with topiramate (Topamax), the fixed combination of topiramate and phentermine (Qsymia), or monotherapy with zonisamide (Zonegran).
