Objective

2

In this study， based on ultra-high performance liquid chromatography-mass spectrometry（UHPLC-MS/MS） and high-throughput transcriptome sequencing technology（RNA-seq）， we investigated the mechanism of Yishen Huashi granules in regulating serum metabolites and renal messenger ribonucleic acid（mRNA） expression to improve diabetic kidney disease（DKD）.

Method

2

SD rats were randomly divided into normal group ， model group and Yishen Huashi granules group， with 8 rats in each group. The rat model of DKD was established by intraperitoneal injection of streptozotocin. Yishen Huashi granules group was given 5.54 g·kg

-1

·d

-1

of Yishen Huashi granules by gavage， and the normal group and the model group were given the same amount of normal saline for 6 weeks. During the experiment， the body weight and blood glucose of rats were monitored， and the rats were anesthetized 24 hours after the last administration， blood was collected from the inferior vena cava， serum was separated， and renal function， blood lipid， and inflammatory indicators were detected. Kidney tissue of rats was fixed in neutral paraformaldehyde， and stained with hematoxylin-eosin（HE）， Masson and periodic acid-Schiff（PAS） to observe the renal pathological changes. UHPLC-MS/MS and RNA-seq were used to identify the changes of serum metabolism and the differences of renal mRNA expression， and real time fluorescence quantitative polymerase chain reaction（Real-time PCR） and Western blot were used to detect the differential mRNA and protein expression in renal tissue to explore the common expression mechanism.

Result

2

Compared with the normal group， rats in the model group showed a decrease in body weight， a significant increase in blood glucose， urinary microalbumin to urinary creatinine ratio（UACR）， blood urea nitrogen（BUN）， cystatin-C（Cys-C），

β

2

-microglobulin（

β

2

-MG）， interleukin-6（IL-6）， triglyceride（TG） and total cholesterol（TC）， and a significant decrease in total superoxide dismutase（T-SOD）（

P

<

0.01）. After the intervention of Yishen Huashi granules， all the indexes were improved to different degrees in rats（

P

<

0.05，

P

<

0.01）. Compared with the normal group， the model group showed renal mesangial stromal hyperplasia， fibrous tissue hyperplasia and tubular vacuolar degeneration. Compared with the model group， the renal pathology of rats in Yishen Huashi granules group was improved to a certain extent. A total of 14 target metabolites and 96 target mRNAs were identified， the target metabolites were mainly enriched in 20 metabolic pathways， including sphingolipid metabolism， glycerophospholipid metabolism， and the biosynthesis of phenylalanine， tyrosine and tryptophan. The target mRNAs were enriched to obtain a total of 21 differential mRNAs involved in the TOP20 pathways closely related to glycolipid metabolism. A total of 6 pathways， glycerophospholipid metabolism， arachidonic acid metabolism， purine metabolism， primary bile acid biosynthesis， ascorbic acid and uronic acid metabolism， and galactose metabolism， were enriched by serum differential metabolites and renal differential mRNAs， among them， there were 7 differential metabolites such as phosphatidylethanolamine（PE） and 7 differential mRNAs such as recombinant adenylate cyclase 3（ADCY3）. Seven differential metabolites had high predictive accuracy as verified by receiver operating characteristic（ROC） curve， and the results of Real-time PCR and Western blot were highly consistent with the sequencing results.

Conclusion

2

Yishen Huashi granules can reduce UACR， BUN and other biochemical indexes， correct the disorder of glucose and lipid metabolism， and improve renal function of DKD rats. And its mechanism may be related to the regulation of the level of PE and other blood metabolites， and expression of Phospho1 and other mRNAs in the kidney， of which six pathways， including glycerophospholipid metabolism， may play an important role.