Effects of Osthole on Inflammatory Gene Expression and Cytokine Secretion in Histamine-Induced Inflammation in the Caco-2 Cell Line

Hyperactivity of the immune system in the gastrointestinal tract leads to the development of chronic, inflammation-associated disorders. Such diseases, including inflammatory bowel disease, are not completely curable, but the specific line of treatment may reduce its symptoms. However, the response to treatment varies among patients, creating a necessity to uncover the pathophysiological basis of immune-mediated diseases and apply novel therapeutic strategies. The present study describes the anti-inflammatory properties of osthole during histamine-induced inflammation in the intestinal Caco-2 cell line. Osthole reduced the secretion of cytokines (CKs) and the expression level of inflammation-associated genes, which were increased after a histamine treatment. We have shown that the secretion of pro-inflammatory CKs (IL-1β, IL-6, IL-8, and TNF-α) during inflammation may be mediated by NFκB, and, after osthole treatment, this signaling pathway was disrupted. Our results suggest a possible role for osthole in the protection against inflammation in the gastrointestinal tract; thus, osthole may be considered as an anti-inflammatory modulator.     

Molecular Insights on the Possible Role of Annexin A2 in COVID-19 Pathogenesis and Post-Infection Complications

Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) has infected >235 million people and killed over 4.8 million individuals worldwide. Although vaccines have been developed for prophylactic management, there are no clinically proven antivirals to treat the viral infection. Continuous efforts are being made all over the world to develop effective drugs but these are being delayed by periodic outbreak of mutated SARS-CoV-2 and a lack of knowledge of molecular mechanisms underlying viral pathogenesis and post-infection complications. In this regard, the involvement of Annexin A2 (AnxA2), a lipid-raft related phospholipid-binding protein, in SARS-CoV-2 attachment, internalization, and replication has been discussed. In addition to the evidence from published literature, we have performed in silico docking of viral spike glycoprotein and RNA-dependent RNA polymerase with human AnxA2 to find the molecular interactions. Overall, this review provides the molecular insights into a potential role of AnxA2 in the SARS-CoV-2 pathogenesis and post-infection complications, especially thrombosis, cytokine storm, and insulin resistance.     

螺旋藻蛋白酶解肽对腹腔粘膜系统的作用

目的：探索螺旋藻(Spirulina)碱性蛋白酶酶解肽对家兔腹腔黏膜系统的作用。方法：采用盐析法从螺旋藻中提取可溶性螺旋藻蛋白,以碱性蛋白酶水解得到螺旋藻蛋白水解物溶液。将所得水解物以3 种方式(口服、腹腔注射、耳静脉注射)对家兔给药,分别在给药3、2、2h 后,用ELISA 试剂盒测定血清中IL-1β、IL-6、IL-12、IFN-γ、TNF-α、IL-1Ra、IL-4、IL-10、TGF- β细胞因子的质量浓度。结果：3 个实验组与正常生理盐水组相比,IL-12 质量浓度均下降,IFN-γ、IL-10 质量浓度均升高;在3 种给药方式中,腹腔注射效果最显著,其他两组细胞因子水平均没有显著性变化。腹腔注射组中炎症细胞因子IL-1β、IL-6、IL-12、TNF-α的质量浓度均显著性降低,抗炎细胞因子IL-1Ra 和IL-4 显著性升高,说明该螺旋藻碱性蛋白酶酶解肽对降低免疫活性起到了一定作用。结论：肠黏膜系统对螺旋藻蛋白酶解肽信号传递主要是通过肠道上皮细胞、内皮细胞及单核/ 巨噬细胞、淋巴细胞之间的信号网络抑制NF- κB 和PKC/p38/MAPK 途径来降低免疫的。这与植物非营养物质能够通过抑制转录因子NF- κB 活性抑制炎症信号级联的作用机制相一致,说明短肽类成分也可以进入体内对机体的慢性疾病甚至癌症起到一定的治疗作用。     

Milk nutrition and childhood epilepsy: An ex vivo study on cytokines and oxidative stress in response to milk protein fractions

We present a pilot study on the effects of milk protein fractions [α_S1-casein (CN), α_S2-CN, κ-CN, β-CN, and a mix of α-lactalbumin (α-LA) and β-lactoglobulin (β-LG)] from different animal species (bovine, ovine, and caprine) on pro- and anti-inflammatory cytokines and oxidative status in cultured peripheral blood mononuclear cells from children with generalized epilepsy. Peripheral blood mononuclear cells (PBMC) were obtained by density gradient from blood of 10 children with generalized epilepsy (5 males; mean age 33.6 ± 5.4 mo) and 10 controls (5 males; mean age 35.6 ± 6.8 mo). Children with epilepsy were grouped according to cytokine levels as follows: children with epilepsy having low levels of cytokines not different from those of control children (LL-EC); children with epilepsy having cytokine levels at least 5-fold higher (medium levels) than those of control children (ML-EC); and children with epilepsy having cytokine levels at least 10-fold higher (high levels) than those of control children (HL-EC). The production of tumor necrosis factor-α (TNF-α), IL-10, IL-6, and IL-1β was studied in cultured PBMC incubated with α_S1-CN, α_S2-CN, κ-CN, β-CN, and a mix of α-LA and β-LG from bovine, caprine, and ovine milks. The levels of reactive oxygen and nitrogen species (ROS/RNS) and catalase activity were assessed in cultured supernatant. In the HL-EC group, β-CN from small ruminant species (ovine and caprine) induced the highest levels of TNF-α, whereas PBMC incubated with α_S2-CN from ovine milk and the mix of β-LG and α-LA from all tested milk species had the lowest levels of TNF-α. Within the HL-EC group, production of IL-1β was higher for bovine and ovine α_S2-CN fractions and lower for caprine and ovine β-CN and κ-CN. In the HL-EC group, IL-6 was higher in cultured PBMC incubated with α_S2-CN from bovine and ovine milk than from caprine milk. The cytokine IL-10 did not differ among milking species. The highest levels of ROS/RNS were found after incubation of PBMC with the β-CN fraction in bovine milk. Catalase activity was higher in PBMC cultured with β-CN isolated from bovine and caprine milk and with α_S1-CN from ovine milk.     

卵转铁蛋白对树突状细胞功能成熟的影响

目的：探究卵转铁蛋白（ovotransferrin,OVT）对树突状细胞（dendritic cells,DCs）功能成熟的影响。方法：通过混合淋巴反应检测OVT对DCs刺激T淋巴细胞增殖能力的影响,酶联免疫吸附分析（enzyme-linkedimmunosorbent assay,ELISA）检测DCs上清液中肿瘤坏死因子-α（tumor necrosis factor-α,TNF-α）、白介素12p70（interleukin-12p70,IL-12p70）和IL-10细胞因子含量,Western blotting检测胞外信号调节激酶（extracellular signalregulated kinase,ERK）、p38丝裂原活化蛋白激酶（p38 mitogen activated protein kinase,p38 MAPK）和c-Jun氨基末端激酶（c-Jun N-terminal kinase,JNK）信号蛋白表达量。结果：OVT可以提高DCs刺激T淋巴细胞增殖的能力,并诱导DCs分泌TNF-α以及IL-12p70,且呈一定的剂量依赖关系。OVT可能是通过激活JNK和p38 MAPK信号通路以及抑制ERK信号通路上调细胞因子TNF-α、IL-12p70表达,从而促进DCs成熟。结论：OVT能促进DCs功能成熟,对机体的免疫具有调节作用。     

长白山榛仁(Corylus heterophylla Fisch.)蛋白酶解物对小鼠免疫功能的影响

本文研究不同水解度的长白山榛仁蛋白酶解物对小鼠免疫功能的影响。按水解时间不同制备六种水解度榛仁蛋白酶解物(DH分别为24.16、29.69、33.22、36.33、38.08和39.57%),给受试组小鼠经口按1.00 g/kg·bw剂量灌胃,灌胃第10、20、30 d后,以小鼠免疫脏器指数,脾淋巴细胞增殖能力,巨噬细胞吞噬活性,血清细胞因子水平(IFN-γ和IL-4),血清碱性磷酸酶活力为指标,研究榛仁蛋白酶解物对小鼠的免疫调节功能。结果表明:水解度33.22%的榛仁蛋白酶解物只显著增加了小鼠胸腺指数(p0.05);水解度为36.33、38.08和39.57%的榛仁蛋白酶解物均能显著或极显著地增加小鼠免疫脏器指数、血清IFN-γ和AKP水平,增强脾淋巴细胞增殖活性和巨噬细胞吞噬活性(p0.05或p0.01)。结论,水解度为36.33、38.08和39.57%的榛仁蛋白酶解物具有增强小鼠免疫功能的作用。本研究为榛仁蛋白开发具有免疫活性的肽类产品提供了实验依据。     

Dietary intervention with sialylated lactulose affects the immunomodulatory activities of mice

Four sialylated lactuloses [N-acetylneuraminic acid-α2,3-lactulose (Neu5Acα2,3lactulose), N-acetylneuraminic acid-α2,6-lactulose (Neu5Acα2,6lactulose), deaminoneuraminc acid-α2,3-lactulose (Kdnα2,3lactulose), and deaminoneuraminc acid-α-2,6-lactulose (Kdnα2,6lactulose)] were reported to modulate the immunity of mice. The influences of cytokine expression, cell immunity, humoral immunity, and nonspecific immunity were investigated in our study using several techniques. Analysis via ELISA showed that cytokine expression was induced by sialylated lactulose treatment consistently in the serum and spleen. Among the 4 tested sialylated lactuloses, Neu5Acα2,6lactulose performed the best, simultaneously and appropriately promoting the expression of proinflammatory and anti-inflammatory factors in the serum and spleen. Kdnα2,3lactulose showed the best antioxidant activity according to detection of the activity of superoxide dismutase, myeloperoxidase, peroxidase, and alkaline phosphatase. Flow cytometry revealed that only Kdnα2,3lactulose significantly boosted the CD3⁺ T lymphocyte ratio similarly to that of lactulose. Analysis of the hemolysin content to characterize humoral immunity revealed that Kdnα2,3lactulose notably increased hemolysin content compared with that in the control group. To evaluate the nonspecific immune effects of the 4 sialylated lactuloses, a fluorescence microsphere phagocytosis assay was used to analyze the phagocytosis of macrophages. Kdnα2,3lactulose still performed the best in enhancing the phagocytosis of macrophages, showing markedly increased phagocytic percentage and phagocytic index values compared with those in the control and lactulose groups. Comparing the differences of these 4 sialylated lactuloses in affecting immunity in mice revealed that Kdnα2,3lactulose had the best overall performance in influencing cytokine expression, cell immunity, humoral immunity, and nonspecific immunity. This study provides critical support for use of sialylated lactuloses as potential immunomodulators in foods.