Intestinal dysbiosis exacerbates the pathogenesis of psoriasis-like phenotype through changes in fatty acid metabolism

The intestinal microbiota has been associated with host immunity as well as psoriasis;however,the mechanism of intestinal microbiota regulating psoriasis needs to be demonstrated systematically.Here,we sought to examine its role and mechanism of action in the pathogenesis of psoriasis.We found that the severity of psoriasis-like skin phenotype was accompanied by changes in the composition of the intestinal microbiota.We performed co-housing and fecal microbial transplantation(FMT)experiments using the K14-VEGF transgenic mouse model of psoriasis and demonstrated that the transfer of intestinal microbiota from mice with severe psoriasis-like skin phenotype exacerbated psoriasiform skin inflammation in mice with mild symptoms,including increasing the infiltration and differentiation of Th17,and increased the abundance of Prevotella,while decreasing that of Parabacteroides distasonis,in the colon.These alterations affected fatty acid metabolism,increasing the abundance of oleic and stearic acids.Meanwhile,gentamicin treatment significantly reduced the abundance of Prevotella and alleviated the psoriasis-like symptoms in both K14-VEGF mice and imiquimod(IMQ)-induced psoriasis-like mice.Indeed,administration of oleic and stearic acids exacerbated psoriasis-like symptoms and increased Th17 and monocyte-derived dendritic cell infiltration in the skin lesion areas in vivo,as well as increased the secretion of IL-23 by stimulating DCs in vitro.At last,we found that,treatment of PDE-4 inhibitor alleviated psoriasis-like phenotype of K14-VEGF mice accompanied by the recovery of intestinal microbiota,including the decrease of Prevotella and increase of Parabacteroides distasonis.Overall,our findings reveal that the intestinal microbiota modulates host metabolism and psoriasis-like skin inflammation in mice,suggesting a new target for the clinical diagnosis and treatment of psoriasis.

Effects of hot air drying temperature and tempering time on the properties of maize starch

Yellow maize as raw materials,hot air drying was used to reduce moisture content,and the tempering was implemented after drying.This study aimed to investigate the effects of hot air drying temperature and tempering time on the properties of maize starch.The wet milling was used to extract maize starch.Starch yield,protein content,amylose and amylopectin content,transparency and coagulation,solubility index and swelling power,color,pasting properties,and gelatinization properties were researched.The results showed that when the hot air temperature increased,the properties such as starch yield,amylopectin content,transparency,solubility,swelling power,whiteness decreased,and properties such as protein content and amylose content,coagulation,gelatinization temperature increased.Compared to drying temperature,tempering time has a less remarkable effect on the maize starch properties.The maize starch with better whiteness,solubility,swelling power could be obtained by adjusting tempering time.