Do you believe there are cases where a person has no problem with absorption, caloric-protein intake, diarrhea, fatigue, reduced strength or physical ability, yet, still has muscle wasting due to HIV actually infecting and then killing off muscle cells similar to the way HIV infects and kills off cd4 cells? I know TNF-alpha is a suspected culprit in wasting, but has anyone investigated the possiblity I propose?
I wandered through a bit of literature to check it out and didn't find anything that suggested your theory has been investigated. There was some information on the potential for HIV to affect the activities of smooth muscle cells (like you find in the heart), but not as a wasting catalyst. So, I would have to say that it may not have been investigated specifically to my knowledge.
Unless the investigation is specific to HIV infection in muscle cells, I think that we are using the more general connection is the inflammatory response that the body produces when faced with infection or injury initiates that hormonal and other changes to protect itself. This includes some breakdown of protein tissues (mostly muscle) to build up an amino acid pool for the body to use to protect itself. The amount of breakdown is related to the severity of the inflammatory response and the infection or injury challenge.