Ectopic colonization of oral bacteria in the intestine drives TH1 cell induction and inflammation

Intestinal colonization by bacteria of oral origin has been correlated with several negative health outcomes, including inflammatory bowel disease. However, a causal role of oral bacteria ectopically colonizing the intestine remains unclear. Using gnotobiotic techniques, we show that strains of Klebsiella spp. isolated from the salivary microbiota are strong inducers of T helper 1 (T_H1) cells when they colonize in the gut. These Klebsiella strains are resistant to multiple antibiotics, tend to colonize when the intestinal microbiota is dysbiotic, and elicit a severe gut inflammation in the context of a genetically susceptible host. Our findings suggest that the oral cavity may serve as a reservoir for potential intestinal pathobionts that can exacerbate intestinal disease.

Phenethyl isothiocyanate Triggers Apoptosis, Combats Oxidative Stress and Inhibits Growth of Ehrlich Ascites Carcinoma Mouse Model

The aim of this study is to investigate the antitumor activity and possible molecular mechanism of Phenethyl isothiocyanate (PEITC) against Ehrlich ascites carcinoma in-vivo and in-vitro. In-vivo, ascetic fluid volume, body weight, serum malondialdehyde (MDA) level and total antioxidant capacity (TAC) were determined using Ehrlich ascites carcinoma (EAC) bearing mice. In-vitro, MTT assay was used. RT-PCR was used to investigate role of PEITC in apoptosis by analyzing the expression of Bax, caspase-9, and Bcl-2 genes. The effect of PEITC on caspase-9 enzyme activity was also tested. PEITC and/or Doxorubicin (Dox) treatment significantly suppressed EAC growth as compared to EAC/oil control mice. PEITC treatment showed a dose-dependent inhibition of EAC cells as indicated by MTT assay. We found that significant increase in MDA level and decrease in TAC caused by Dox treatment were significantly reduced by combination with PEITC treatment. Bax, caspase-9 genes' expression and caspase-9 enzymatic activity were significantly increased, while Bcl-2 gene expression was significantly decreased in PEITC treated mice. PEITC may act as a promising anticancer agent either alone or more effectively in combination with Dox through apoptotic cell death induction.

Cepharanthine and Piperine ameliorate diabetic nephropathy in rats: role of NF-κB and NLRP3 inflammasome

AIMS

Hyperglycemia leads to elevation of oxidative stress and proinflammatory cytokines which are the main causes of diabetic nephropathy (DN). NLRP3 inflammasome and thioredoxin-interacting protein (TXNIP) are recently assumed to participate in the development of DN. We aimed to investigate the effects of Cepharanthine (CEP), Piperine (Pip) and their combination in streptozotocin (STZ)-induced DN focusing on their role to modulate NLRP3 and TXNIP induced inflammation.

MAIN METHODS

Diabetic rats were treated with intraperitoneal (i.p.) injection of CEP (10mg/kg/day), Pip (30mg/kg/day) or their combination for 8weeks. Nuclear factor kappa B (NF-κB), tumor necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β) were assessed by ELISA technique. TXNIP and NLRP3 genes expressions were evaluated by real time-PCR.

KEY FINDINGS

Diabetic rats showed significant increase in renal TXNIP and NLRP3 expression. CEP, Pip or their combination significantly decreased TXNIP and NLRP3 expression in diabetic kidneys. Hyperglycemia induced NF-κB activation leading to increased IL-1β and TNF-α levels. CEP, Pip or their combination showed significant inhibition of NF-κB together with decreased IL-1β and TNF-α levels in diabetic rats. Also, diabetic rats showed significant decrease in creatinine clearance and increase in blood glucose, serum creatinine, blood urea nitrogen, malondialdehyde, proteinuria, and kidney weight to body Weight ratio. All of these changes were reversed by CEP, Pip or their combination.

SIGNIFICANCE

The antioxidant and anti-inflammatory effects of CEP and Pip which were accompanied by inhibition of NF-κB and NLRP3 activation might be helpful mechanisms to halt the progression of DN.

Dysbiosis of salivary microbiota in inflammatory bowel disease and its association with oral immunological biomarkers

Analysis of microbiota in various biological and environmental samples under a variety of conditions has recently become more practical due to remarkable advances in next-generation sequencing. Changes leading to specific biological states including some of the more complex diseases can now be characterized with relative ease. It is known that gut microbiota is involved in the pathogenesis of inflammatory bowel disease (IBD), mainly Crohn's disease and ulcerative colitis, exhibiting symptoms in the gastrointestinal tract. Recent studies also showed increased frequency of oral manifestations among IBD patients, indicating aberrations in the oral microbiota. Based on these observations, we analyzed the composition of salivary microbiota of 35 IBD patients by 454 pyrosequencing of the bacterial 16S rRNA gene and compared it with that of 24 healthy controls (HCs). The results showed that Bacteroidetes was significantly increased with a concurrent decrease in Proteobacteria in the salivary microbiota of IBD patients. The dominant genera, Streptococcus, Prevotella, Neisseria, Haemophilus, Veillonella, and Gemella, were found to largely contribute to dysbiosis (dysbacteriosis) observed in the salivary microbiota of IBD patients. Analysis of immunological biomarkers in the saliva of IBD patients showed elevated levels of many inflammatory cytokines and immunoglobulin A, and a lower lysozyme level. A strong correlation was shown between lysozyme and IL-1β levels and the relative abundance of Streptococcus, Prevotella, Haemophilus and Veillonella. Our data demonstrate that dysbiosis of salivary microbiota is associated with inflammatory responses in IBD patients, suggesting that it is possibly linked to dysbiosis of their gut microbiota.