Antimicrobial peptides in the duodenum at the acute and convalescent stages in patients with diarrhea due to Vibrio cholerae O1 or enterotoxigenic Escherichia coli infection.
Shirin. Tahmina T; Rahman. Arman A; Danielsson. Åke Å; Uddin. Taher T; Bhuyian. Taufiqur Rahman TR; Sheikh. Alaullah A; Qadri. Syed Saleheen SS; Qadri. Firdausi F; Hammarström. Marie-Louise ML
Key Findings
- LL‑37 peptide levels fall during the acute stage of cholera/ETEC infection while its mRNA stays unchanged
- hBD‑2 mRNA and stool peptide levels rise sharply in the acute phase
- Paneth cells store more HD‑5 peptide during recovery and in healthy controls
Practical Outcomes
- The study mainly confirms that LL‑37 levels dip during acute diarrheal disease, so there’s no new supplement or dosage advice for biohackers. Maintaining overall gut health may help keep innate peptides like LL‑37 stable, but no specific protocol changes are suggested.
Summary
During a severe diarrhea infection like cholera, the gut’s natural antimicrobial peptide LL‑37 drops in the lining even though the body keeps making its messenger RNA, while another peptide, hBD‑2, spikes and shows up in stool. This shows the gut’s innate defenses shift during illness, but it doesn’t give new ways to boost LL‑37 directly.
Abstract
Patients with acute watery diarrhea caused by Vibrio cholerae O1 or enterotoxigenic Escherichia coli (ETEC) were analyzed for innate immune factors produced by the epithelium during the disease process. Duodenal biopsies were obtained from study participants at the acute (day 2) and convalescent (day 21) stages of disease. Levels of α-defensin (HD-5 and -6), β-defensin (hBD-1-4), and cathelicidin (LL-37) mRNAs were determined by real-time qRT-PCR. hBD-2, HD-5, LL-37 peptides were analyzed in duodenal epithelium by immunomorphometry. Concentration of hBD-2 in stool was determined by ELISA. Specimens from healthy controls were also analyzed. hBD-2 mRNA levels were significantly increased at acute stage of diarrhea; hBD-2 peptide was detected in fecal specimens but barely in duodenal epithelium at acute stage. Immunomorphometry analysis showed that Paneth cells contain significantly higher amounts of HD-5 pre/propeptide at convalescence (P<0.01) and in healthy controls (P<0.001) compared to acute stage, LL-37 peptide levels also decreased at acute stage while mRNA levels remained unchanged. mRNA expression levels of the other antimicrobial peptides remained unchanged with higher levels of α-defensins than β-defensins. V. cholerae induced an innate immune response at the acute stage of disease characterized by increased expression of hBD-2, and continued expression of hBD-1, HD-5-6, and LL-37.
Study Information
pubmed
2011
2011-07-18T00:00:00.000Z
10.1016/j.micinf.2011.06.014
26
46