Binding of Cry1Ab toxin, a Bacillus thuringiensis insecticidal toxin, to proteins of the bovine intestinal epithelial cell: An in vitro study

The mode of inactivation of probiotic bacteria may profoundly affect their immune-modulatory properties to the point of reversal of effects in in vitro human intestinal epithelial-like cell cultures (Caco-2). To further investigate the influence of inactivation treatment on cytokine production, three probiotic strains were evaluated—live, heat-inactivated, and formalininactivated strains—for their impact on interleukin (IL) 6, IL-8, and IL-10 production in Caco-2–leucocyte cocultures. The tested bacteria induced strain-specific production of IL-6, IL-8, and IL-10. No suppressive effects on cytokine synthesis were observed. Live microorganisms seemed to be slightly more potent inducers of cytokine production than nonviable strains, but differences to inactivated bacteria were not statistically significant. Our results indicate that heat and formalin treatments of probiotic microorganisms are equivalent inactivation methods in terms of induction of IL-6, IL-8, and IL-10 production in Caco-2–peripheral blood mononuclear cell cocultures and do not invert immune-modulatory effects.

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Effects of botulinum toxin A and papaverine on human saphenous vein and internal mammary artery grafts: an in vitro study

Archives of Medical Science ◽

10.5114/aoms/110157 ◽

2021 ◽

Author(s):

Ipek Duman ◽

Ömer Tanyeli ◽

Yuksel Dereli ◽

Pembe Oltulu ◽

Hatice Toy ◽

...

Keyword(s):

Botulinum Toxin ◽

Saphenous Vein ◽

Internal Mammary Artery ◽

Botulinum Toxin A ◽

In Vitro Study ◽

Vitro Study ◽

Arterial Graft ◽

Toxin A ◽

Internal Mammary

IntroductionAutologous saphenous vein (SV) and internal mammary artery (IMA) are used as bypass conduits during coronary artery bypass graft surgery. Vasospasm of the arterial and venous grafts may constitute a significant clinical problem. Pretreatment with a vasodilator drug of the graft ex vivo or intraluminal injection before implantation may be used for spasm prophylaxis. This in-vitro study was designed to assess the vasoactive effects and time-dependent changes of botulinum toxin A (BTX-A) and papaverine pretreatment on vasospasm of human SV and IMA grafts. Also histomorphology of the vessels were assessed.Material and methodsSV and IMA segments were suspended in organ baths and isometric contraction responses to two different concentrationsof 5-hydroxytryptamine (5-HT) and endothelin-1 (ET-1) were recorded after incubation with two different concentrations of BTX-A and papaverine at two time points (0 hours and 2nd hour).ResultsThe results suggest that; 1) incubation with BTX-A and papaverine relaxes both SV and IMA rings contracted with 5-HT and ET-1, 2) duration of the relaxant effect of BTX-A lasts longer than papaverine, 3) no apparent histomorphologic changes are observed in the grafts under light microscopy.ConclusionsThis study demonstrates that in human SV and IMA grafts, pretreatment with both BTX-A and papaverine are safe and have a potent inhibitory effect depending on the vessel and vasoconstrictor agent. Long lasting vasodilatory effect of BTX-A on vascular smooth muscle may provide promising results for preventing venous and arterial graft spasm.

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