Lactobacillus paracasei F19 versus placebo for the prevention of proton pump inhibitor-induced bowel symptoms: a randomized clinical trial.

BACKGROUND: Proton pump inhibitors may foster intestinal dysbiosis and related bowel symptoms. AIM: To evaluate the effect of Lactobacillus paracasei F19 on bowel symptom onset in patients on long-term proton pump inhibitors. METHODS: In this randomized, double-blind, placebo-controlled study, patients with typical gastroesophageal reflux disease symptoms receiving pantoprazole 40 mg/d for six months were randomly assigned to receive: (A) Lactobacillus paracasei F19 bid for three days/week for six months; (B) placebo bid for three days/week for six months; (C) Lactobacillus paracasei F19 bid for three days/week for three months and placebo bid for three days/week for the following three months; (D) placebo bid for three days/week for three months and Lactobacillus paracasei F19 bid for three days/week for the following three months. Bloating, flatulence, abdominal pain and bowel habit were assessed monthly. RESULTS: 100/312 patients were enrolled. In the parallel groups, the treatment-by-time interaction affected bloating (p = 0.015), while Lactobacillus paracasei F19 treatment alone affected flatulence (p = 0.011). Moreover, the treatment-by-time interaction significantly affected the mean score of bloating (p = 0.01) and flatulence (p < 0.0001), the mean stool form (p = 0.03) and mean stool frequency/week (p = 0.016). Analysis of the cross-over groups, limited to the first three months because of carry-over effect, confirmed these results. CONCLUSION: Lactobacillus paracasei F19 supplementation prevents bowel symptom onset in patients on long-term proton pump inhibitors.

Vitamin B12 supplementation improves rates of sustained viral response in patients chronically infected with hepatitis C virus.

BACKGROUND: In vitro, vitamin B12 acts as a natural inhibitor of hepatitis C virus (HCV) replication. OBJECTIVE: To assess the effect of vitamin B12 on virological response in patients with chronic HCV hepatitis naïve to antiviral therapy. METHODS: Ninety-four patients with chronic HCV hepatitis were randomly assigned to receive pegylated interferon α plus ribavirin (standard-of-care; SOC) or SOC plus vitamin B12 (SOC+B12). Viral response-namely, undetectable serum HCV-RNA, was evaluated 4 weeks after starting treatment (rapid viral response), 12 weeks after starting treatment (complete early viral response) and 24 or 48 weeks after starting treatment (end-of-treatment viral response) and 24 weeks after completing treatment (sustained viral response (SVR)). Genotyping for the interleukin (IL)-28B polymorphism was performed a posteriori in a subset (42/64) of HCV genotype 1 carriers. RESULTS: Overall, rapid viral response did not differ between the two groups, whereas the rates of complete early viral response (p=0.03), end-of-treatment viral response (p=0.03) and SVR (p=0.001) were significantly higher in SOC+B12 patients than in SOC patients. In SOC+B12 patients, the SVR rate was also significantly higher in carriers of a difficult-to-treat genotype (p=0.002) and in patients with a high baseline viral load (p=0.002). Distribution of genotype IL-28B did not differ between the two groups. At multivariate analysis, only easy-to-treat HCV genotypes (OR=9.00; 95% CI 2.5 to 37.5; p=0.001) and vitamin B12 supplementation (OR=6.9; 95% CI 2.0 to 23.6; p=0.002) were independently associated with SVR. CONCLUSION: Vitamin B12 supplementation significantly improves SVR rates in HCV-infected patients naïve to antiviral therapy.

Protective effects of Lactobacillus paracasei F19 in a rat model of oxidative and metabolic hepatic injury.

The liver is susceptible to such oxidative and metabolic stresses as ischemia-reperfusion (I/R) and fatty acid accumulation. Probiotics are viable microorganisms that restore the gut microbiota and exert a beneficial effect on the liver by inhibiting bacterial enzymes, stimulating immunity, and protecting intestinal permeability. We evaluated Lactobacillus paracasei F19 (LP-F19), for its potential protective effect, in an experimental model of I/R (30 min ischemia and 60 min reperfusion) in rats fed a standard diet or a steatogen [methionine/choline-deficient (MCD)] diet. Both groups consisted of 7 sham-operated rats, 10 rats that underwent I/R, and 10 that underwent I/R plus 8 wk of probiotic dietary supplementation. In rats fed a standard diet, I/R induced a decrease in sinusoid perfusion (P < 0.001), severe liver inflammation, and necrosis besides an increase of tissue levels of malondialdehyde (P < 0.001), tumor necrosis factor-alpha (P < 0.001), interleukin (IL)-1beta (P < 0.001), and IL-6 (P < 0.001) and of serum levels of transaminase (P < 0.001) and lipopolysaccharides (P < 0.001) vs. sham-operated rats. I/R also induced a decrease in Bacterioides, Bifidobacterium, and Lactobacillus spps (P < 0.01, P < 0.001, and P < 0.001, respectively) and an increase in Enterococcus and Enterobacteriaceae (P < 0.01 and P < 0.001, respectively) on intestinal mucosa. The severity of liver and gut microbiota alterations induced by I/R was even greater in rats with liver inflammation and steatosis, i.e., MCD-fed animals. LP-F19 supplementation significantly reduced the harmful effects of I/R on the liver and on gut microbiota in both groups of rats, although the effect was slightly less in MCD-fed animals. In conclusion, LP-F19 supplementation, by restoring gut microbiota, attenuated I/R-related liver injury, particularly in the absence of steatosis.

Chemoprevention of gastric cancer: role of COX-2 inhibitors and other agents.

Despite the decrease in incidence, gastric cancer remains the second leading cause of cancer-related death worldwide. Prevention is likely to be the most effective means of not only reducing the incidence but also mortality from this disease. The term 'chemoprevention' has been referred to the prevention of cancer using specific agents to suppress or reverse the carcinogenic process. In recent years, attention has been focused on the anticancer properties of non-steroidal anti-inflammatory drugs (NSAIDs), Helicobacter pylori eradication therapy and diet life-style. In vitro and in vivo studies show that widespread and long-term use of NSAIDs may be adopted in the healthy population for gastric chemoprevention. Albeit, enthusiasm has been thwarted by the potential toxic effects, i.e., risk of peptic ulcer disease. The new NSAIDs, selective cyclooxygenase-2 inhibitors, causing less injury to the mucosa of the upper gastrointestinal tract may be a valid alternative. However, fundamental questions such as safety, efficacy, mechanisms of actions, and optimal treatment regimens need to be defined. H. pylori triggers gastric carcinogenesis, however, cost-effect analyses suggest that only a subgroup of H. pylori-infected subjects present beneficial changes following eradication therapy. Diet plays an important role in the pathogenesis of gastric cancer either increasing the risks of or protecting against, cancer development. Thus, a reasonable suggestion for the general population is a natural chemoprevention based on life-style 'eat to live, not live to eat'.