Vol. 9, Issue 3, Part A (2025)

Background: Partial hepatectomy (PHx) is the treatment of choice for many malignant liver diseases. Liver regeneration post-PHx is a highly coordinated process involving pro- inflammatory cytokines. Lactococcus lactis D4 is a probiotic with immunomodulatory potential, suggested to enhance liver regeneration. Objective: To determine the effect of Lactococcus lactis D4 on liver regeneration rate (LRR) and hepatocyte proliferation index (Ki67) in Wistar rats after PHx. Methods: Thirty male Wistar rats were randomly assigned into five groups: Sham (laparotomy only), Control (PHx only), P1 (LL before PHx), P2 (LL after PHx), and P3 (LL before & after PHx). LL D4 was administered orally at 10⁹ CFU/ml. At week 4 post-surgery, rats were sacrificed, and liver tissues were analyzed for LRR and Ki67 index. Data were analyzed using ANOVA and LSD post-hoc tests (p<0.05). Results: LL D4 significantly increased Ki67 index compared to the control group (p<0.05), with the highest proliferation observed in P3. No significant difference was found in LRR among groups (p>0.05). Conclusion: Oral administration of LL D4 promotes hepatocyte proliferation after PHx without significantly altering LRR, indicating its potential as a pro-inflammatory immunomodulator in liver regeneration.