title: Live and heat-killed Lactobacillus rhamnosus GG upregulate gene expression of pro-inflammatory cytokines in 5-fluorouracil-pretreated Caco-2 cells.
abstract: OBJECTIVE
  This study investigates whether post-chemotherapeutic use of live and heat-killed Lactobacillus rhamnosus GG can modulate the expression of three pro-inflammatory cytokines in 5-fluorouracil (5-FU)-induced intestinal mucositis in vitro.
  
  
  METHODS
  Live L. rhamnosus GG and heat-killed L. rhamnosus GG were observed using scanning electron microscopy. To establish the duration required for optimal expression of tumor necrosis factor-α (TNF-α), monocyte chemotactic protein-1 (MCP-1), and interleukin-12 (IL-12), 5 μM of 5-FU was selected to treat 10-day-old Caco-2 cells for 4, 6, 8, and 24 h. Caco-2 cells were treated with 5-FU (5 μM) for 4 h, followed by the administration of live L. rhamnosus GG (multiplicity of infection = 25), and heat-killed L. rhamnosus GG for 2 and 4 h. Finally, total cellular RNA was isolated to quantify mRNA expression of TNF-α, MCP-1, and IL-12 using real-time PCR.
  
  
  RESULTS
  The results demonstrated that heat-killed L. rhamnosus GG remained structurally intact with elongation. A biphasic upregulated expression of TNF-α, MCP-1, and IL-12 was observed in 5-FU-treated Caco-2 cells at 4 and 24 h. Compared to non-L. rhamnosus GG controls in 5-FU-pretreated Caco-2 cells, a 2-h treatment of heat-killed L. rhamnosus GG significantly upregulated the MCP-1 expression (p < 0.05), and both live and heat-killed L. rhamnosus GG treatments lasting 4 h upregulated the TNF-α and MCP-1 expression (p < 0.05). Only live L. rhamnosus GG upregulated the IL-12 expression (p < 0.05).
  
  
  CONCLUSIONS
  Post-chemotherapeutic use of live or heat-killed L. rhamnosus GG can upregulate the gene expression of 5-FU-induced pro-inflammatory cytokines in Caco-2 cells. Human intestinal epithelium may be vulnerable to the post-chemotherapeutic use of L. rhamnosus GG in 5-FU-induced mucositis that requires further in vivo studies for clarification.
authors: Division of Pediatric Gastroenterology and Hepatology, Department of Pediatrics, Shuang Ho Hospital, Taipei Medical University, 291, Jhong Jheng Road, Jhong Ho District, Taipei, 23561, Taiwan, sbfang@tmu.edu.tw.
authors: Shiuh-Bin
authors: SB
authors: Fang
authors: Hsin-Yu
authors: HY
authors: Shih
authors: Chih-Hung
authors: CH
authors: Huang
authors: Li-Ting
authors: LT
authors: Li
authors: Chia-Chun
authors: CC
authors: Chen
authors: Hsu-Wei
authors: HW
authors: Fang
mesh_terms: D018938:Caco-2 Cells; D018932:Chemokine CCL2 / Q000096:biosynthesis / Q000235:genetics; D016207:Cytokines / Q000096:biosynthesis* / Q000235:genetics*; D005472:Fluorouracil / Q000494:pharmacology*; D006801:Humans; D018664:Interleukin-12 / Q000096:biosynthesis / Q000235:genetics; D052201:Lacticaseibacillus rhamnosus; D019936:Probiotics / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000235:genetics; D015854:Up-Regulation / Q000187:drug effects
chemical_list: C111835:CCL2 protein, human; D018932:Chemokine CCL2; D016207:Cytokines; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D018664:Interleukin-12; D005472:Fluorouracil