Morphine-like Novel Compounds for the Treatment of Depressive Symptoms

Depression is a severe mental disorder characterized by a major imbalance between the levels of neurotransmitters. US11534436 B2 discloses an efficient amount of mu -opioid receptor agonists or their pharmaceutically acceptable salt for efficient treatment of depression. The patent discloses a few new compounds among which compounds 1, 2, 3, 4, and 5 as well as derivatives of basic nucleus A have good mu -opioid receptor agonist activity without risks of opioid addiction or development of addiction withdrawal symptoms. The compounds displayed E-max of 5% to 45% in a GTP gamma S binding assay while one of the derivatives displayed Emax of 15% to 35% in a GTP gamma S binding assay. The patent further discloses different embodiments with different potentials. The administration of an effective dose in rats resulted in 125% to 300% efflux of dopamine of baseline. At a dosage of 1-10 mg/kg, the embodiments do not diminish the thermal pain in rodents. Although the patent explored new mu -opioid receptor agonists for the treatment of depressive symptoms, the exhaustive evaluation of toxicity and further mechanisms need to be explored via in vivo models.