The efficacy of Omega-3 polyunsaturated fatty acids for severe burn patients: A systematic review and trial sequential meta-analysis of randomized controlled trials.

BACKGROUND & AIMS: Severe burns lead to metabolic changes, systemic inflammatory response syndrome, and multiple organ dysfunction syndrome. Omege-3 polyunsaturated fatty acids (PUFAs) have anti-inflammatory properties. In the absence of substantial evidence for use on major burns, we systematically reviewed the efficacy of omega-3 PUFAs for patients with severe burns. METHODS: We comprehensively searched MEDLINE, Web of Science, Embase, Cochrane Library, China National Knowledge Internet, Wang Fang Data, Chinese Biomedicine Database, and Science Direct databases to collect randomised controlled trials of omega-3 PUFAs administered to patients with burns from January 2000 to June 2023. Two researchers independently screened the literatures, extracted the data, and assessed the risk of bias in the included studies. The outcomes were mortality, the risk of severe sepsis, septic shock, and multiple organ dysfunction syndrome. Data synthesis was conducted using Review Manager. Trial sequential analyses (TSA) for outcomes were performed. RESULTS: Three randomised controlled trials involving 140 patients were included. Of these, 71 patients received omega-3 PUFAs. The results showed that omega-3 PUFAs significantly reduced the incidence of severe sepsis, septic shock, multiple organ dysfunction syndrome (RR = 0.38, 95 % CI [0.19, 0.75], P = 0.005), C-reactive protein levels (MD = -39.70[-81.63, 2.23], P = 0.06), and improved respiratory outcomes. However, there was no difference in 14-day mortality (RR = 1.10, 95%CI [0.59, 2.05], P = 0.75). TSA showed that the results for the incidence of severe sepsis, septic shock, multiple organ dysfunction syndrome are insufficient and inconclusive. CONCLUSIONS: Omega-3 PUFAs may reduce inflammatory response and risk of sepsis, septic shock, and multiple organ dysfunction syndrome in severe burns patients and may shorten hospital stay but cannot reduce risk of death. Due to the limitation of the quantity and quality of the included studies, the evidence level is low, and the conclusions need to be verified by larger scale and higher quality randomised controlled trials.

Long noncoding RNA H19 regulates degeneration and regeneration of injured peripheral nerves.

Our previous studies have shown that long noncoding RNA (lncRNA) H19 is upregulated in injured rat sciatic nerve during the process of Wallerian degeneration, and that it promotes the migration of Schwann cells and slows down the growth of dorsal root ganglion axons. However, the mechanism by which lncRNA H19 regulates neural repair and regeneration after peripheral nerve injury remains unclear. In this study, we established a Sprague-Dawley rat model of sciatic nerve transection injury. We performed in situ hybridization and found that at 4-7 days after sciatic nerve injury, lncRNA H19 was highly expressed. At 14 days before injury, adeno-associated virus was intrathecally injected into the L4-L5 foramina to disrupt or overexpress lncRNA H19. After overexpression of lncRNA H19, the growth of newly formed axons from the sciatic nerve was inhibited, whereas myelination was enhanced. Then, we performed gait analysis and thermal pain analysis to evaluate rat behavior. We found that lncRNA H19 overexpression delayed the recovery of rat behavior function, whereas interfering with lncRNA H19 expression improved functional recovery. Finally, we examined the expression of lncRNA H19 downstream target SEMA6D, and found that after lncRNA H19 overexpression, the SEMA6D protein level was increased. These findings suggest that lncRNA H19 regulates peripheral nerve degeneration and regeneration through activating SEMA6D in injured nerves. This provides a new clue to understand the role of lncRNA H19 in peripheral nerve degeneration and regeneration.