Human Gut Microbiome Before and After Bariatric Surgery in Obese Patients with and Without Type 2 Diabetes.

BACKGROUND: Bariatric surgery, a significant intervention for obesity, may influence weight loss through changes in gut microbiota, particularly the Firmicutes and Bacteroidetes. This study explores these potential shifts and their metabolic implications. MATERIALS: We conducted a cross-sectional study involving patients who had undergone bariatric surgery. Stool samples were collected at baseline, 3 months, and 6 months post-operation. We performed DNA extraction and quantified the bacterial phyla Firmicutes and Bacteroidetes to assess changes in the gut microbiota over time. RESULTS: Our research revealed a significant alteration in the gut microbiota following bariatric surgery. In diabetic individuals, there was a marked increase in the average number of Firmicutes bacteria at both 3 and 6 months post-operation, compared to pre-surgery levels. In contrast, non-diabetic subjects experienced a notable decrease in Firmicutes during the same timeframe. Regarding Bacteroidetes bacteria, the trend was reversed; diabetic patients showed a significant reduction, while non-diabetics exhibited an increase after the surgery. These findings highlight the dynamic changes in gut microbiota composition associated with bariatric surgery and its potential link to metabolic changes post-operation. CONCLUSION: These findings suggest that obesity alters the gut's microbial composition. The observed bacterial fluctuations, particularly in the dominant Firmicutes and Bacteroidetes groups, are likely contributors to the weight loss experienced post-surgery. This alteration in gut bacteria underscores the complex interplay between microbiota and metabolic health, highlighting potential avenues for therapeutic intervention.

The investigation of the frequency of the alpha-1-antitrypsin phenotype in patients with liver cirrhosis.

OBJECTIVES: Alpha-1-antitrypsin (AAT) has different phenotypes. Evidence suggests that the abundance of each of these phenotypes may be associated with a disease. The purpose of this study was to evaluate the frequency of AAT phenotypes in patients with liver cirrhosis as well as in healthy individuals. METHODS: In this study, 42 patients with liver cirrhosis were selected. The results of the previous research done by the researcher on healthy individuals were used to construct the control group. After obtaining informed consent, 5 mL of fasting venous blood sample was taken, and phenotypes were analyzed by isoelectric focusing. Data were analyzed using Chi-square and Fisher's exact tests at a significant level of 0.05. RESULTS: The results of this study indicated that all 42 healthy subjects had an MM allele (100%). However, among 42 patients, 35 (83.3%) had an MM allele, 5 (11.9%) had an MS allele, and 2 (4.8%) had MZ allele. The difference between the two groups was significant (p=0.02). There was no difference between men and women in the allele type (p=0.557). CONCLUSIONS: This study revealed that MS and MZ alleles were observed only in patients with liver cirrhosis, and none of these alleles were found in healthy subjects. Therefore, MS and MZ alleles can be further investigated as risk factors for liver cirrhosis.

Are RIG-1 and MDA5 Expressions Associated with Chronic HBV Infection?

Melanoma differentiation-associated protein 5 (MDA5) and retinoic acid-inducible gene 1 (RIG-1) as the pattern recognition receptors play important roles in viral mRNA recognition. Chronic HBV-infected (CHB) patients are unable to properly respond to hepatitis B virus (HBV). Therefore, the aim of the present study was to evaluate the mRNA levels of MDA5 and RIG-1 in the peripheral blood immune cells of CHB patients in comparison to healthy controls. In this cross-sectional study, the mRNA levels of MDA5 and RIG-1 were examined in 60 CHB patients and 60 healthy controls using the real-time polymerase chain reaction (PCR) technique. Our results showed that mRNA levels of MDA5 and RIG-1 were significantly decreased and increased, respectively, in CHB patients when compared to healthy controls. Our results also revealed that mRNA levels of MDA5 and RIG-1 were not altered among CHB patients with various states of e-antigen of hepatitis B and HBV-DNA viral loads. According to the results presented here, it may be concluded that downregulation of MDA5 may be a responsible mechanism from several reasons, which leads to HBV persistence in CHB patients.

Decreased expressions of Toll-like receptor 9 and its signaling molecules in chronic hepatitis B virus-infected patients.

CONTEXT: Toll-like receptors (TLRs) play crucial roles in immune responses, especially innate immunity, against viral infections. Toll-like receptor 9 recognizes intracellular viral double-strand DNA, which leads to the activation of nuclear factor B (NF-κB) through the myeloid differentiation primary response 88 (MYD88) pathway. Defects in the expression of TLR9 and its signaling molecules may cause attenuated immune responses against hepatitis B virus. OBJECTIVE: To determine expression levels of TLR9 messenger RNA along with MYD88, interleukin 1 receptor-associated kinase 1 (IRAK1), tumor necrosis factor receptor-associated factor 6 (TRAF6), and NF-κB in the peripheral blood mononuclear cells obtained from chronic hepatitis B virus (CHB)-infected patients. DESIGN: In this study, 60 CHB patients and 60 healthy controls were recruited and the expression of TLR9 and its downstream signaling molecules was examined by real-time polymerase chain reaction techniques using ß-actin as a housekeeping gene. RESULTS: Our results showed that expression of TLR9, MYD88, IRAK1, TRAF6, and NF-κB in peripheral blood mononuclear cells of CHB patients was significantly decreased in comparison with healthy controls. CONCLUSIONS: According to our results, it appears that CHB patients are unable to appropriately express genes in the TLR9 pathway, which may impede immune responses against hepatitis B virus infection. These results suggest a mechanism that may partially explain the fact that immune responses are disrupted in CHB patients.

Downregulation of CCR5 expression on the peripheral blood CD8+ T cells of southeastern Iranian patients with chronic hepatitis B infection.

Studies indicated that CC receptor 5 (CCR5), as a receptor for CC ligand 3, CCL4, and CCL5, plays important roles in the recruitment of T cytotoxic lymphocytes to the liver of chronic HBV (CHB)-infected patients. The main purpose of this study was to investigate the expression levels of CCR5 on the CD8(+) T lymphocytes of CHB patients. This clinical study was performed on 63 CHB patients and 96 healthy controls. Flow cytometric analysis was performed to examine the expression of CCR5 on CD8(+) T cells of CHB patients. Real-time PCR was also used for HBV-DNA quantification. The results of our study demonstrated that CCR5 expressing T cytotoxic cells were decreased significantly in CHB patients in comparison to healthy control. Based on our results, it can be concluded that the percent of CCR5(+)/CD8(+) T cells in Iranian CHB patients is significantly decreased, hence their migration to the infected liver, and HBV eradication from the hepatocytes is disrupted.