Efficacy of probiotics against dental caries in children: a systematic review and meta-analysis.

Dental caries causes serious consequences and the financial burden of society especially in children with high morbidity rate. Here we carried out a meta-analysis to systematically evaluate the efficacy of probiotics against dental caries in children. Forty-three RCTs were eligible for this meta-analysis after searching the PubMed, Cochrane and Web of Science from the inception through October 2021. Pooled estimates demonstrated that treatment with probiotics significantly reduced noncavitated (dicdas2-6mft) (SMD = -0.18, 95% CI: -0.3 to -0.06, p = 0.002) and cavitated (dicdas5-6mft) carious lesions in children (SMD = -0.32, 95% CI: -0.5 to 0.14, p = 0.0004). Probiotics also reduced prevalence of noncavitated (dicdas2-6mft) carious lesions (RR = 0.8, 95% CI: 0.67 to-0.97, p = 0.02). Salivary Streptococcus mutans was declined after intervention (SMD = -1.17, 95% CI: -1.85 to -0.5, p = 0.0007), while Lactobacillus counts were upregulated (SMD = 1.19, 95% CI: 0.46-1.92, p = 0.001). However, no significant effects in total bacteria counts and salivary pH were observed. Our findings suggest that probiotics especially Lactobacillus could be a promising therapeutic strategy for clinical applications in children dental caries.

Microbial treatment of alcoholic liver disease: A systematic review and meta-analysis.

Background and aims: Alcoholic liver disease (ALD) is characterized by impaired liver function due to chronic alcohol consumption, even fatal in severe cases. We performed a meta-analysis to determine whether microbial agents have therapeutic potential for ALD and elucidate the underlying mechanisms. Methods and results: Forty-one studies were eligible for this meta-analysis after searching the PubMed, Cochrane, and Embase databases. The combined analysis showed that microbial therapy significantly decreased hepatic enzymatic parameters, including alanine transaminase [standardized mean difference (SMD): -2.70, 95% confidence interval (CI): -3.33 to -2.07], aspartate aminotransferase (SMD: -3.37, 95% CI: -4.25 to -2.49), γ-glutamyl transpeptidase (SMD: -2.07, 95% CI: -3.01 to -1.12), and alkaline phosphatase (SMD: -2.12, 95% CI: -3.32 to -0.92). Microbial agents endotoxin to enter the portal circulation and increasing reduced total cholesterol (SMD = -2.75, 95%CI -4.03 to -1.46) and triglycerides (SMD = -2.64, 95% CI: -3.22 to -2.06). Microbial agents increased amounts of the beneficial flora Lactobacillus (SMD: 4.40, 95% CI: 0.97-7.84) and Bifidobacteria (SMD: 3.84, 95% CI: 0.22-7.45), Bacteroidetes (SMD: 2.51, 95% CI: 0.29-4.72) and decreased harmful Proteobacteria (SMD: -4.18, 95% CI: -6.60 to -1.77), protecting the integrity of the intestinal epithelium and relieving endotoxin (SMD: -2.70, 95% CI: -3.52 to -2.17) into the portal vein, thereby reducing the production of inflammatory factors such as tumor necrosis factor-α (SMD: -3.35, 95% CI: -4.31 to -2.38), interleukin-6 (SMD: -4.28, 95% CI: -6.13 to -2.43), and interleukin-1ß (SMD: -4.28, 95% CI: -6.37 to -2.19). Oxidative stress was also relieved, as evidenced by decreased malondialdehyde levels (SMD: -4.70, 95% CI: -6.21 to -3.20). Superoxide dismutase (SMD: 2.65, 95% CI: 2.16-3.15) and glutathione levels (SMD: 3.80, 95% CI: 0.95-6.66) were elevated. Conclusion: Microbial agents can reverse dysbiosis in ALD, thus significantly interfering with lipid metabolism, relieving inflammatory response and inhibiting oxidative stress to improve liver function.

A Meta-Analysis of Microbial Therapy Against Metabolic Syndrome: Evidence From Randomized Controlled Trials.

Background and aims: Metabolic syndrome (MetS), accompanied with significant intestinal dysbiosis, causes a great public health burden to human society. Here, we carried out a meta-analysis to qualify randomized controlled trials (RCTs) and to systematically evaluate the effect of microbial therapy on MetS. Methods and results: Forty-two RCTs were eligible for this meta-analysis after searching the PubMed, Cochrane, and Embase databases. Pooled estimates demonstrated that treatment with microbial therapy significantly reduced the waist circumference (WC) (SMD = -0.26, 95% CI -0.49, -0.03), fasting blood glucose (FBG) (SMD = -0.35, 95% CI -0.52, -0.18), total cholesterol (TC) (SMD = -0.36, 95% CI -0.55, -0.17), low-density lipoprotein cholesterol (LDL-C) (SMD = -0.42, 95% CI -0.61, -0.22), and triacylglycerol (TG)(SMD = -0.38, 95% CI -0.55, -0.20), but increased the high-density lipoprotein cholesterol (HDL-C) (SMD = 0.28, 95% CI.03, 0.52). Sensitivity analysis indicated that after eliminating one study utilizing Bifidobacteriumlactis, results became statistically significant in diastolic blood pressure (DBP) (SMD = -0.24, 95% CI -0.41, -0.07) and in Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) (SMD = -0.28, 95% CI -0.54, -0.03), while the body mass index (BMI) showed significant difference after eliminating one study utilizing oat bran (SMD = -0.16, 95% CI -0.31, -0.01). There was still no significant effect in systolic blood pressure (SBP) and in hemoglobin A1c (HbA1c%). Conclusion: In patients with MetS, the conditioning with microbial therapy notably improves FBG, TC, TG, HDL-C, LDL-C, WC, BMI (except for the study using oat bran), HOMA-IR, and DBP (except for the Study using Bifidobacteriumlactis), however, with no effect in SBP and in HbA1c%.