Piatek Karina, Gushchina Valeriya, Kleinwächter Ava, Kupper Nadja, Mesteri Ildiko, Elajnaf Taha, Iamartino Luca, Salzmann Martina, Müller Christian, Manhardt Teresa, Vlasaty Andrea, Kallay Enikö, Schepelmann Martin
Institute for Pathophysiology and Allergy Research, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria.
Pathologie Überlingen, 88662 Überlingen, Germany.
Nutrients. 2024 Dec 18;16(24):4362. doi: 10.3390/nu16244362.
BACKGROUND/OBJECTIVES: The extracellular calcium-sensing receptor (CaSR) is a multifunctional receptor proposed as a possible drug target for inflammatory bowel disease. We showed previously that CaSR inhibition with NPS 2143, a negative allosteric modulator of the CaSR, somewhat ameliorated the symptoms of chemically induced severe colitis in mice. However, it was unclear whether the potential of CaSR inhibition to reduce colitis may have been overshadowed by the severity of the induced inflammation in our previous study. Therefore, we tested if CaSR inhibition could prevent medium-grade colitis.
Female BALB/c mice were treated with NPS 2143 or a vehicle prior to the induction of colitis with 2.5% DSS. On the day of sacrifice, colons and plasma were collected. The histology score was determined based on hematoxylin-eosin-stained sections. Mucin content, proliferation (Ki67), and immune cell infiltration (CD3 and CD20) were quantified based on immunostainings. Gene expression was measured by RT-qPCR.
Treatment with NPS 2143 had no effect on the clinical symptom score of the mice. However, the colons of the mice in the treated group were significantly longer ( < 0.05), and NPS 2143 significantly reduced colon ulceration ( < 0.05). The treatment also significantly reduced the expression of COX2 in the proximal colon and IL-22 in the distal colon. The proliferation of cells in the lymph nodes was significantly lower after the treatment, but no difference was observed in the epithelial cells.
In summary, while NPS 2143 had an anti-inflammatory effect on medium-grade colitis, this effect appeared to be milder than in severe colitis, as observed previously, indicating that the effectiveness of CaSR inhibition as an anti-inflammatory measure in the colon is proportional to disease severity.
背景/目的：细胞外钙敏感受体（CaSR）是一种多功能受体，被认为是炎性肠病可能的药物靶点。我们之前表明，使用CaSR的负变构调节剂NPS 2143抑制CaSR，可在一定程度上改善化学诱导的小鼠重度结肠炎症状。然而，在我们之前的研究中，尚不清楚CaSR抑制减轻结肠炎的潜力是否可能被诱导炎症的严重程度所掩盖。因此，我们测试了CaSR抑制是否能预防中度结肠炎。
在用2.5%葡聚糖硫酸钠（DSS）诱导结肠炎之前，对雌性BALB/c小鼠用NPS 2143或赋形剂进行处理。在处死当天，收集结肠和血浆。根据苏木精-伊红染色切片确定组织学评分。基于免疫染色对粘蛋白含量、增殖（Ki67）和免疫细胞浸润（CD3和CD20）进行定量。通过逆转录定量聚合酶链反应（RT-qPCR）测量基因表达。
用NPS 2143处理对小鼠的临床症状评分没有影响。然而，治疗组小鼠的结肠明显更长（P<0.05），并且NPS 2143显著减少了结肠溃疡（P<0.05）。该治疗还显著降低了近端结肠中COX2的表达以及远端结肠中IL-22的表达。治疗后淋巴结中细胞的增殖显著降低，但上皮细胞中未观察到差异。
总之，虽然NPS 2143对中度结肠炎有抗炎作用，但正如之前所观察到的，这种作用似乎比重度结肠炎中的作用更轻微，这表明CaSR抑制作为结肠抗炎措施的有效性与疾病严重程度成正比。
