Cyclic vomiting syndrome in multisystem mitochondrial disorder.

Vomiting is a complex physiological response to expel harmful or irritating substances from the body. It's a defensive mechanism triggered by stimuli like poisons, microbial toxins, cytotoxic drugs, and mechanical abdominal distension. The process is centrally coordinated by the vomiting (or emetic) center located in the medulla of the brainstem. This area, rich in muscarinic M1, histamine H1, neurokinin 1 (NK1), and serotonin 5-HT3 receptors, coordinates the act of vomiting through...

A single mitochondrion is a bean-shaped organelle enclosed by a double-membrane system. The outer membrane of mitochondria is smooth and contains many porins - the integral membrane transporters. Porins enable free diffusion of ions and small uncharged molecules through the outer mitochondrial membrane but limit the transport of molecules larger than 5000 Daltons. Further, the outer mitochondrial membrane forms a unique structure called membrane contact sites with other subcellular organelles,...

The mitochondrial electron transport chain (ETC) is the main energy generation system in the eukaryotic cells. However, mitochondria also produce cytotoxic reactive oxygen species (ROS) due to the large electron flow during oxidative phosphorylation. While Complex I is one of the primary sources of superoxide radicals, ROS production by Complex II is uncommon and may only be observed in cancer cells with mutated complexes.
ROS generation is regulated and maintained at moderate levels necessary...

Dopamine receptor antagonists, also known as antipsychotic agents, are critical in managing chemotherapy-induced vomiting. These antiemetic agents block dopamine receptors in the chemoreceptor trigger zone (CTZ), inhibiting signal transmission to the vomiting center. Antipsychotic agents encompass phenothiazines (PTZ), butyrophenones, benzamides, and thienobenzodiazepines (Zyprexa), which are utilized for their antiemetic and sedative properties.
Phenothiazines, such as prochlorperazine...

Gastrointestinal or GI motility disorders are characterized by irregular gastrointestinal tract movements, disrupting food transit from the mouth to the anus. They are caused by damage or dysfunction in gut muscles or nerves. These disorders can cause symptoms such as severe constipation, diarrhea, abdominal pain, and swallowing difficulties. Disorders can affect any segment of the GI tract and range widely in severity, from common conditions like GERD to life-threatening conditions like...