The edible cyanobacterium Spirulina platensis and its chief biliprotein C-Phycocyanin have shown protective activity in animal models of diverse human health diseases, often reflecting antioxidant and anti-inflammatory effects. The beneficial effects of C-Phycocyanin seem likely to be primarily attributable to its covalently attached chromophore Phycocyanobilin (PCB). Within cells, biliverdin is generated from free heme and it is subsequently reduced to bilirubin. Although bilirubin can function as an oxidant scavenger, its potent antioxidant activity reflects its ability to inactivate some isoforms of NADPH oxidase. Free bilirubin can also function as an agonist for the aryl hydrocarbon receptor (AhR); this may explain its ability to promote protective Treg activity in cellular and rodent models of inflammatory disease. AhR agonists also promote transcription of the gene coding for Nrf-2, and hence can up-regulate phase 2 induction of antioxidant enzymes, such as HO-1. Hence, it is proposed that C-Phycocyanin/PCB chiefly exert their protective effects via inhibition of NADPH oxidase activity, as well as by AhR agonism that both induces Treg activity and up-regulates phase 2 induction. This simple model may explain their potent antioxidant/antiinflammatory effects. Additionally, PCB might mimic biliverdin in activating anti-inflammatory signaling mediated by biliverdin reductase. This essay reviews recent research in which CPhycocyanin and/or PCB, administered orally, parenterally, or intranasally, have achieved marked protective effects in rodent and cell culture models of Ischemic Stroke and Multiple Sclerosis, and suggests that these agents may likewise be protective for Alzheimer’s disease, Parkinson’s disease, and in COVID-19 and its neurological complications.

可食用蓝藻螺旋藻及其主要胆蛋白 C-藻蓝蛋白在多种人类健康疾病的动物模型中显示出保护活性，通常反映抗氧化和抗炎作用。C-藻蓝蛋白的有益作用似乎主要归因于其共价连接的发色团藻蓝蛋白 (PCB)。在细胞内，胆绿素由游离血红素产生，随后还原为胆红素。尽管胆红素可以作为氧化剂清除剂，但其强大的抗氧化活性反映了其使某些 NADPH 氧化酶同种型失活的能力。游离胆红素还可以作为芳烃受体 (AhR) 的激动剂；这可以解释它在炎症性疾病的细胞和啮齿动物模型中促进保护性 Treg 活性的能力。AhR 激动剂还促进编码 Nrf-2 的基因的转录，因此可以上调抗氧化酶（例如 HO-1）的 2 期诱导。因此，提出 C-藻蓝蛋白/PCB 主要通过抑制 NADPH 氧化酶活性以及通过诱导 Treg 活性和上调第 2 期诱导的 AhR 激动剂发挥其保护作用。这个简单的模型可以解释它们强大的抗氧化/抗炎作用。此外，PCB 可能在激活由胆绿素还原酶介导的抗炎信号方面模拟胆绿素。本文回顾了最近的研究，其中 CPhycocyanin 和/或 PCB，口服、肠胃外或鼻内给药，在缺血性中风和多发性硬化的啮齿动物和细胞培养模型中取得了显着的保护作用，