Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 May 22;13(1):8241.
doi: 10.1038/s41598-023-35019-5.

Intestine and brain TLR-4 modulation following N-acetyl-cysteine treatment in NEC rodent model

Ron Beloosesky  1   2 , Ola Gutzeit  3 , Yuval Ginsberg  3 , Nizar Khatib  3 , Michael G Ross  4 , Zeev Weiner  3 , Osnat Zmora  5   6
Affiliations

Intestine and brain TLR-4 modulation following N-acetyl-cysteine treatment in NEC rodent model

Ron Beloosesky et al. Sci Rep. .

Abstract

Necrotizing enterocolitis (NEC) brain injury is mediated through Toll-like receptor 4 (TLR4) on the intestinal epithelium and brain microglia. Our aim was to determine whether postnatal and/or prenatal NAC can modify NEC associated intestinal and brain TLR4 expression and brain glutathione levels in a rat model of NEC. Newborn Sprague-Dawley rats were randomized into three groups: Control (n = 33); NEC (n = 32)-hypoxia and formula feeding; and NEC-NAC (n = 34)-received NAC (300 mg/kg IP) in addition to NEC conditions. Two additional groups included pups of dams treated once daily with NAC (300 mg/kg IV) for the last 3 days of pregnancy: NAC-NEC (n = 33) or NAC-NEC-NAC (n = 36) with additional postnatal NAC. Pups were sacrificed on the fifth day, and ileum and brains harvested for TLR-4 and glutathione protein levels. Brain and ileum TLR-4 protein levels were significantly increased in NEC offspring as compared to control (brain 2.5 ± 0.6 vs. 0.88 ± 0.12 U and ileum 0.24 ± 0.04 vs. 0.09 ± 0.01, p < 0.05). When NAC was administered only to dams (NAC-NEC) a significant decrease in TLR-4 levels was demonstrated in both offspring brain (1.53 ± 0.41 vs. 2.5 ± 0.6 U, p < 0.05) and ileum (0.12 ± 0.03 vs. 0.24 ± 0.04 U, p < 0.05) as compared to NEC. The same pattern was demonstrated when NAC was administered only or postnatally. The decrease in brain and ileum glutathione levels observed in NEC offspring was reversed with all NAC treatment groups. NAC reverses the increase in ileum and brain TLR-4 levels and the decrease in brain and ileum glutathione levels associated with NEC in a rat model, and thus may protect from NEC associated brain injury.

PubMed Disclaimer

Conflict of interest statement

The authors declare no competing interests.

Figures

Figure 1
Figure 1
Flowchart of the different study groups. IV intravenous, NAC N-acetyl cysteine, NEC necrotizing enterocolitis, IP intraperitoneal, NS normal saline.
Figure 2
Figure 2
Offspring brain TLR-4 protein levels in Groups 1–5. NEC pups had significantly increased brain TLR-4 levels as compared with control pups; NAC to pregnant dams, offspring, or both dams and offspring significantly decreased offspring LLR-4 levels as compared with NEC pups (CTL, NEC, NEC-NAC, NAC-NEC and NAC-NEC-NAC). *Significant difference (P < 0.05) from NEC. #Significant difference (P < 0.05) from NAC-NEC. ^Significant difference (P < 0.05) from NEC-NAC. NAC N-acetyl cysteine, NEC necrotizing enterocolitis, TLR-4 Toll-like receptor 4.
Figure 3
Figure 3
Offspring ileum TLR-4 protein levels in Groups 1–5. NEC pups had significantly increased ileal TLR-4 levels as compared with control pups; NAC to pregnant dams, offspring, or both dams and offspring significantly decreased offspring LLR-4 levels as compared with NEC pups (CTL, NEC, NEC-NAC, NAC-NEC and NAC-NEC-NAC). *Significant difference (P < .05) from NEC. #Significant difference (P < 0.05) from NAC-NEC. NAC N-acetyl cysteine, NEC necrotizing enterocolitis, TLR-4 Toll-like receptor 4.
Figure 4
Figure 4
Offspring brain glutathione protein levels in Groups 1–5. NEC pups had significantly decreased brain glutathione levels as compared with control pups; NAC to pregnant dams, offspring, or both dams and offspring significantly increased offspring brain glutathione levels as compared with NEC pups. CTL, NEC, NEC-NAC, NAC-NEC and NAC-NEC-NAC. *Significant difference (P < 0.05) from NEC. #Significant difference (P < 0.05) from NAC-NEC. ~ Significant difference (P < 0.05) from NAC-NEC-NAC. NAC N-acetyl cysteine, NEC necrotizing enterocolitis.
Figure 5
Figure 5
Offspring ileum glutathione protein levels in Groups 1–5. NEC pups had significantly decreased ileum glutathione levels as compared with control pups; NAC to pregnant dams, offspring, or both dams and offspring significantly increased offspring ileum glutathione levels as compared with NEC pups. CTL, NEC, NEC-NAC, NAC-NEC and NAC-NEC-NAC. *Significant difference (P < 0.05) from NEC. #Significant difference (P < 0.05) from NAC-NEC. @Significant difference (P < 0.05) from CTL. NAC N-acetyl cysteine, NEC necrotizing enterocolitis.
See this image and copyright information in PMC

References

    1. Mihi B, Good M. Impact of toll-like receptor 4 signaling in necrotizing enterocolitis: The state of the science. Clin. Perinatol. 2019;46:145–157. doi: 10.1016/j.clp.2018.09.007. - DOI - PMC - PubMed
    1. Neu J. Necrotizing enterocolitis: The search for a unifying pathogenic theory leading to prevention. Pediatr. Clin. North Am. 1996;43:409–432. doi: 10.1016/s0031-3955(05)70413-2. - DOI - PMC - PubMed
    1. Hunter CJ, Upperman JS, Ford HR, Camerini V. Understanding the; susceptibility of the premature infant to necrotizing enterocolitis (NEC) Pediatr. Res. 2008;63:117–123. doi: 10.1203/PDR.0b013e31815ed64c. - DOI - PubMed
    1. Blakely ML, et al. NEC Subcommittee of the NICHD Neonatal Research Network. Postoperative outcomes of extremely low birth-weight infants with necrotizing enterocolitis or isolated intestinal perforation: A prospective cohort study by the NICHD Neonatal Research Network. Ann. Surg. 2005;241:984–9. doi: 10.1097/01.sla.0000164181.67862.7f. - DOI - PMC - PubMed
    1. Balance WA, Dahms BB, Shenker N, Kliegman RM. Pathology of neonatal necrotizing enterocolitis: A ten-year experience. J. Pediatr. 1990;117:S6–13. doi: 10.1016/s0022-3476(05)81124-2. - DOI - PubMed