NSAID-enteropathy and intestinal microbes

Use of Saccharomyces boulardii CNCM I-745 as therapeutic strategy for prevention of nonsteroidal anti-inflammatory drug-induced intestinal injury

BACKGROUND AND PURPOSE

Nonsteroidal anti-inflammatory drugs (NSAIDs) can be associated with severe adverse digestive effects. This study examined the protective effects of the probiotic Saccharomyces boulardii CNCM I-745 in a rat model of diclofenac-induced enteropathy.

EXPERIMENTAL APPROACH

Enteropathy was induced in 40-week-old male rats by intragastric diclofenac (4 mg·kg-1 BID for 14 days). S. boulardii CNCM I-745 (3 g·kg-1 BID by oral gavage) was administered starting 14 days before (preventive protocol) or along with (curative protocol) diclofenac administration. Ileal damage, inflammation, barrier integrity, gut microbiota composition and toll-like receptors (TLRs)-nuclear factor κB (NF-κB) pathway were evaluated.

KEY RESULTS

Diclofenac elicited intestinal damage, along with increments of myeloperoxidase, malondialdehyde, tumour necrosis factor and interleukin-1β, overexpression of TLR2/4, myeloid differentiation primary response 88 (Myd88) and NF-κB p65, increased faecal calprotectin and butyrate levels, and decreased blood haemoglobin levels, occludin and butyrate transporter monocarboxylate transporter 1 (MCT1) expression. In addition, diclofenac provoked a shift of bacterial taxa in both faecal and ileal samples. Treatment with S. boulardii CNCM I-745, in both preventive and curative protocols, counteracted the majority of these deleterious changes. Only preventive administration of the probiotic counteracted NSAID-induced decreased expression of MCT1 and increase in faecal butyrate levels. Occludin expression, after probiotic treatment, did not significantly change.

CONCLUSIONS AND IMPLICATIONS

Treatment with S. boulardii CNCM I-745 prevents diclofenac-induced enteropathy through anti-inflammatory and antioxidant activities. Such effects are likely to be related to increased tissue butyrate bioavailability, through an improvement of butyrate uptake by the enteric mucosa.

Non-steroidal anti-inflammatory drugs caused an outbreak of inflammation and oxidative stress with changes in the gut microbiota in rainbow trout (Oncorhynchus mykiss)

One of the main contributors to pharmaceutical pollution of surface waters are non-steroidal anti-inflammatory drugs (NSAIDs) that contaminate the food chain and affect non-target water species. As there are not many studies focusing on toxic effects of NSAIDs on freshwater fish species and specially effects after dietary exposure, we selected rainbow trout (Oncorhynchus mykiss) as the ideal model to examine the impact of two NSAIDs - diclofenac (DCF) and ibuprofen (IBP). The aim of our study was to test toxicity of environmentally relevant concentrations of these drugs together with exposure doses of 100× higher, including their mixture; and to deepen knowledge about the mechanism of toxicity of these drugs. This study revealed kidneys as the most affected organ with hyalinosis, an increase in oxidative stress markers, and changes in gene expression of heat shock protein 70 to be signs of renal toxicity. Furthermore, hepatotoxicity was confirmed by histopathological analysis (i.e. dystrophy, congestion, and inflammatory cell increase), change in biochemical markers, increase in heat shock protein 70 mRNA, and by oxidative stress analysis. The gills were locally deformed and showed signs of inflammatory processes and necrotic areas. Given the increase in oxidative stress markers and heat shock protein 70 mRNA, severe impairment of oxygen transport may be one of the toxic pathways of NSAIDs. Regarding the microbiota, an overgrowth of Gram-positive species was detected; in particular, significant dysbiosis in the Fusobacteria/Firmicutes ratio was observed. In conclusion, the changes observed after dietary exposure to NSAIDs can influence the organism homeostasis, induce ROS production, potentiate inflammations, and cause gut dysbiosis. Even the environmentally relevant concentration of NSAIDs pose a risk to the aquatic ecosystem as it changed O. mykiss health parameters and we assume that the toxicity of NSAIDs manifests itself at the level of mitochondria and proteins.

COVID-19 and the kidney: time to take a closer look

Although coronavirus disease (COVID-19) is primarily a respiratory disease, the kidney may be among the target organs of infection with severe acute respiratory syndrome coronavirus 2 (SARS-COV-2). Independently of baseline kidney function, acute kidney injury (AKI) is a common complication of COVID-19, associated with increased mortality and morbidity. Most frequently, COVID-19 causes acute tubular necrosis; however, in some cases, collapsing focal segmental glomerulosclerosis and direct viral tropism of the kidneys have also been documented. AKI secondary to COVID-19 has a multi-factorial origin. Even mild impairment of renal function is an independent risk factor for COVID-19 infection, hospitalisation and mortality. Dialysis patients also carry an increased risk of other severe COVID-related complications, including arrhythmias, shock, acute respiratory distress syndrome and acute heart failure. In such patients, COVID-19 may even present with atypical clinical symptoms, including gastrointestinal disorders and deterioration of mental status. More research is needed on the exact effects of SARS-CoV-2 on the kidneys. Finally, it remains to be proven whether the outcome of patients with kidney disease may be improved with anticipated vaccination programmes.

Nerolidol: a potential approach in rheumatoid arthritis through reduction of TNF-α, IL-1β, IL-6, NF-kB, COX-2 and antioxidant effect in CFA-induced arthritic model

Rheumatoid arthritis is primarily associated with inflammation and increased level of proinflammatory cytokines which are released by immune cells, macrophages or activation of arachidonic acid metabolism. The expression of these cytokines, oxidative free radicals and the activation of COX-2 enzymes are crucial targets for chronic inflammation. On the basis of established anti-inflammatory efficacy of nerolidol, the primary study was further appraised to determine its approach against Freund's complete adjuvant (CFA) rheumatoid model. Arthritis was induced by inoculation of 0.1 mL CFA injection into the left hind footpad of rats. Anti-arthritic potential of nerolidol (at 200, 400 and 800 mg/kg doses) was assessed by measuring the paw volume, body weight, serum analysis, histopathological and radiographs of ankle joints. Expressions of cytokine's panels such as IL-10, IL-4, COX-2, NF-kB, TNF-α, IL-6, PGE-2 and IL-1β were determined by real-time qPCR. Antioxidant enzyme analyses were conducted by measuring the SOD, POD and catalase activity from serum and equated with arthritic control group. Nerolidol prevented body weight loss, stabilized biochemical and haematological homeostasis and significantly reduced the paw volume. Furthermore, X-ray and histopathological assessment of ankle joints showed an improvement in the joint structure of rats treated with nerolidol. Besides that, overexpression of gene pointers like TNF-α, IL-1β, IL-6, NF-kB, PGE-2 and COX-2 in CFA-treated control rats were also reversed with nerolidol. This anti-arthritic mechanism was further supported by the increased level of IL-10, IL-4 and serum antioxidant activity. The present findings demonstrate that nerolidol reduced adjuvant arthritis by downregulating the proinflammatory cytokines and upregulating the aforementioned anti-inflammatory cytokines and may be used as a therapeutic substance for the management of human rheumatoid arthritis.