Although protein drugs are powerful biologic therapeutics, they cannot be delivered orally because their large size and hydrophilicity limit their absorption across the intestinal epithelium. One potential solution is the incorporation of permeation enhancers into oral protein formulations; however, few have advanced clinically due to toxicity concerns surrounding chronic use. To better understand these concerns, we conducted a 30-day longitudinal study of daily oral permeation enhancer use in mice and resultant effects on intestinal health. Specifically, we investigated three permeation enhancers: sodium caprate (C₁₀), an industry standard, as well as 1-phenylpiperazine (PPZ) and sodium deoxycholate (SDC). Over 30 days of treatment, all mice gained weight, and none required removal from the study due to poor health. Furthermore, intestinal permeability did not increase following chronic use. We also quantified the gene expression of four tight junction proteins (claudin 2, claudin 3, ZO-1, and JAM-A). Significant differences in gene expression between untreated and permeation enhancer-treated mice were found, but these varied between treatment groups, with most differences resolving after a 1-week washout period. Immunofluorescence microscopy revealed no observable differences in protein localization or villus architecture between treated and untreated mice. Overall, PPZ and SDC performed comparably to C₁₀, one of the most clinically advanced enhancers, and results suggest that the chronic use of some permeation enhancers may be therapeutically viable from a safety standpoint.

中文翻译：

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长期每日口服肠道渗透增强剂对小鼠安全有效


尽管蛋白质药物是强大的生物疗法，但它们不能口服给药，因为它们的大尺寸和亲水性限制了它们穿过肠上皮的吸收。一种潜在的解决方案是将渗透促进剂掺入口服蛋白质制剂中；然而，由于长期使用的毒性问题，很少有临床进展。为了更好地了解这些问题，我们对小鼠每日口服渗透促进剂的使用及其对肠道健康的影响进行了为期 30 天的纵向研究。具体来说，我们研究了三种渗透促进剂：工业标准癸酸钠 (C ₁₀ )，以及 1-苯基哌嗪 (PPZ) 和脱氧胆酸钠 (SDC)。经过 30 天的治疗，所有小鼠的体重都增加了，并且没有一只小鼠因健康状况不佳而需要从研究中剔除。此外，长期使用后肠道通透性并未增加。我们还定量了四种紧密连接蛋白（紧密连接蛋白 2、紧密连接蛋白 3、ZO-1 和 JAM-A）的基因表达。未治疗小鼠和渗透增强剂治疗小鼠之间的基因表达存在显着差异，但这些差异在治疗组之间有所不同，大多数差异在 1 周的清除期后消失。免疫荧光显微镜显示，治疗和未治疗的小鼠之间的蛋白质定位或绒毛结构没有明显差异。总体而言，PPZ 和 SDC 的表现与临床上最先进的增强剂之一 C ₁₀相当，结果表明，从安全角度来看，长期使用某些渗透增强剂可能在治疗上可行。