In this video, we're going to talk about how lipid A can cause septic shock. Recall from some of our previous lesson videos that lipid A is the toxic portion of endotoxin or lipopolysaccharide. Recall that the endotoxin or lipopolysaccharide is found in the outer membrane of gram-negative bacteria. Now if these gram-negative bacteria are lysed or ruptured, then that could cause the release of the lipid A molecule. If lipid A is released and infects the bloodstream, it could initiate a culmination of systematic responses referred to as septic shock. Septic shock can include symptoms such as fever, anemia, or low red blood cell count, weakness, diarrhea, and inflammation. Lipid A can also cause life-threatening cytokine storms, which, recall, is just a massive release of cytokines or chemicals used for communication signals during immune responses. By causing this cytokine storm, it could result in the rapid dilation of the blood vessels or rapid enlargement of the blood vessels, and that can significantly decrease blood pressure. Septic shock can have physiological effects on the heart, the vascular system, and other body organs as well. Ultimately, since septic shock is life-threatening, it could potentially lead to death.
If we take a look at our image down below, notice on the left-hand side we're showing a person with lungs infected with some kind of gram-negative bacteria. Notice that if the gram-negative bacteria enter the bloodstream, then, when these gram-negative bacteria are lysed or rupture, they could release lipid A into the bloodstream. If the infection enters into the bloodstream, it could potentially move to other organs as well. Organs such as the brain, kidneys, liver, and heart are all examples of organs that could be infected. This could lead to, once again, septic shock. Severe physiological effects on these different organs mean that in many cases, patients are not able to recover and could lead to death.
This concludes our brief lesson on how lipid A causes septic shock and how that can be life-threatening. We will be able to get some practice applying these concepts as we move forward and learn more. I'll see you all in our next video.