Does transforming growth factor-β inhibit nitric oxide synthesis and prevent septic shock?

Objective

We measured nitrite/nitrate (NOx) levels and transforming growth factor beta (TGF-β) levels in septic shock, and assessed these factors during the onset of shock.

Patients

Twenty-two patients with sepsis not complicated by shock and 23 patients with septic shock.

Measurements and main results

NOx levels were significantly higher in the septic shock group than in the sepsis-alone group. NOx levels were significantly higher in the group that died than in the group that survived. TGF-β levels were significantly higher in the sepsis-alone group than in the septic shock group. TGF-β levels were significantly higher in the group that survived than in the group that died. Twenty-one (80.8 %) of the 26 patients with NOx levels of 92.9 μmol/l or more (mean + standard deviation in the sepsis group without shock) had sepsis complicated by shock, as opposed to only 2 (10.5%) of the 19 patients with NOx levels below 92.9 μmol/l, and the rate of occurrence of shock as a complication of sepsis was significantly higher when the NOx level was 92.9 μmol/l or more. Two (12.5%) of the 16 patients with TGF-β levels of 19.3 ng/ml or more (mean + standard deviation in the septic shock group) had sepsis complicated by shock, versus 21 (72.4%) of the 29 patients with TGF-β levels below 19.3 ng/ml, and the rate of occurrence of shock as a complication was significantly higher among the patients with TGF-β levels below 19.3 ng/ml. There was a significant negative correlation between NOx levels and TGF-β levels.

Conclusion

NO is involved in the pathogencsis of septic shock. TGF-β appears to inhibit NO production, and may act to prevent septic shock.