## 4 Discussion  
A meta-analysis of probiotic supplementation showed that hypercholesterolemia, TC, and LDL-C decreased after probiotic supplementation [23]. Similarly, the authors of [24] also reported that probiotic _Lactobacillus_ consumption for 12 weeks reduced serum lipid levels, especially for LDL-C, and increased HDL-C significantly. The current study results of the double-blind, placebo-controlled randomized clinical trial with 1.25 \(\times\) 10\({}^{10}\) CFU/day of _L. paracasei_ HII01 also support the notion that probiotic supplementation reduces TC, TGs, and LDL-C in adult subjects characterized by moderate hypercholesterolemia. Furthermore,  
Figure 3: Estimated means \(\pm\) the standard error of the mean (mixed model repeated measures analysis with correction for differences in the baseline values). TCH (**a**), HDL-C (**b**), Lactic acid (**c**), and TNF-\(\alpha\) (**d**). *\(p\)\(<\) 0.05 between the groups at the visit. \({}^{\ddagger}\)\(p\)\(<\) 0.05 overall difference between the groups. their HDL-C levels significantly increased at the end of treatment compared with the placebo group. Some of the probiotics have bile salt hydrolase activity, with synthesized bile salt enzymes used to deconjugate bile salts into bile acids that are excreted with feces. The increase in bile salt synthesis results in more cholesterol as a substrate to synthesize bile salt [25]. The supplementation of _L. paracasei_ HII01 also showed a significant decrease in MDA, a decomposition product of peroxid oxidized polyunsaturated fatty acid involved with the decreasing of LDL. Oxidant LDL, due to the high LDL levels in the bloodstream, leads to inflammation by the release of TNF-\(\alpha\), the generation of foam cells to develop atherosclerosis, and cholesterol efflux [7]. Moreover, _L. paracasei_ significantly increases GSH, the critical antioxidant in protecting the cell from oxidative stress damage [26]. According to [9], probiotics have a role in oxidative defense by scavenging hydroxyl radicals via the stimulation of various antioxidant enzymes and the production of metabolites with antioxidant capacity such as GSH. Moreover, the total antioxidant capacity (TAC) increased after the supplementation of _L. paracasei_ HII01 compared with the baseline. The chelating of the metal ions of probiotics also affects the increase in TAC. The chelating of metal ions also assists in reducing the lipid peroxidation involved in lowering inflammation, although it is unclear what factors are responsible for this process. _Lactobacillus_ and _Bifidobacterium_ are the major microorganisms that produce short-chain fatty acids (SCFAs) through the fermentation process [27]. SCFAs benefit the host by regulating colonic pH, ion transport, gene expression, the improvement of the epithelial barrier, and potent inflammatory action. The supplementation of _Lactobacillus_ strains significantly increases the formation of butyrate and propionate [28]. Furthermore, the increase in short-chain fatty acid production is related to decreasing blood cholesterol due to disturbed reverse cholesterol transport (RCT) [29]. There are significant differences in the fecal SCFAs between the two groups of the study (receiving probiotics and receiving the placebo), i.e., acetate content was dominant over the others [30]. However, in the current study, the propionic acids showed significant differences between the two groups, whereas the lactic acids showed substantial increase after _L. paracasei_ supplementation, as well as showing significant differences between the groups. Probiotics produce an immunomodulatory effect by stimulating the release of cytokines--including interleukins (ILs), tumor necrosis factors (TNFs), interferons ( IFNs), and chemokines--from the immune cells of the host.