Effects of Polygonum cuspidatum on AMPK-FOXO3α Signaling Pathway in Rat Model of Uric Acid-Induced Renal Damage.

BACKGROUND: To observe the effects of Chinese medicine (CM) Polygonum cuspidatum (PC) on adenosine 5'-monophosphate-activated protein kinase (AMPK), forkhead box O3α (FOXO3α), Toll-like receptor-4 (TLR4), NACHT, LRR and PYD domains-containing protein 3 (NLRP3), and monocyte chemoattractant protein-1 (MCP-1) expression in a rat model of uric acid-induced renal damage and to determine the molecular mechanism. METHODS: A rat model of uric acid-induced renal damage was established, and rats were randomly divided into a model group, a positive drug group, and high-, medium-, and low-dose PC groups (n=12 per group). A normal group (n=6) was used as the control. Rats in the normal and model groups were administered distilled water (10 mL•kg-1) by intragastric infusion. Rats in the positive drug group and the high-, medium-, and low-dose PC groups were administered allopurinol (23.33 mg•kg-1), and 7.46, 3.73, or 1.87 g•kg-1•d-1 PC by intragastric infusion, respectively for 6 to 8 weeks. After the intervention, reverse transcription polymerase chain reaction, Western blot, enzyme linked immunosorbent assay, and immunohistochemistry were used to detect AMPK, FOXO3α, TLR4, NLRP3, and MCP-1 mRNA and protein levels in renal tissue or serum. RESULTS: Compared with the normal group, the mRNA transcription levels of AMPK and FOXO3α in the model group were significantly down-regulated, and protein levels of AMPKα1, pAMPKα1 and FOXO3α were significantly down-regulated at the 6th and 8th weeks (P<0.01 or P<0.05). The mRNA transcription and protein levels of TLR4, NLRP3 and MCP-1 were significantly up-regulated (P<0.01 or P<0.05). Compared with the model group, at the 6th week, the mRNA transcription levels of AMPK in the high- and medium-dose groups, and protein expression levels of AMPKα1, pAMPKα1 and FOXO3α in the high-dose PC group, AMPKα1 and pAMPKα1 in the mediumdose PC group, and pAMPKα1 in the low-dose PC group were significantly up-regulated (P<0.01 or P<0.05); the mRNA transcription and protein levels of TLR4 and NLRP3 in the 3 CM groups, and protein expression levels of MCP-1 in the medium- and low-dose PC groups were down-regulated (P<0.01 or P<0.05). At the 8th week, the mRNA transcription levels of AMPK in the high-dose PC group and FOXO3α in the medium-dose PC group, and protein levels of AMPKα1, pAMPKα1 and FOXO3α in the 3 CM groups were significantly up-regulated (P<0.01 or P<0.05); the mRNA transcription levels of TLR4 in the medium- and low-dose PC groups, NLRP3 in the high- and low-dose PC groups and MCP-1 in the medium- and low-dose PC groups, and protein expression levels of TLR4, NLRP3 and MCP-1 in the 3 CM groups were down-regulated (P<0.01 or P<0.05). CONCLUSION: PC up-regulated the expression of AMPK and its downstream molecule FOXO3α and inhibited the biological activity of TLR4, NLRP3, and MCP-1, key signal molecules in the immunoinflammatory network pathway, which may be the molecular mechanism of PC to improve hyperuricemia-mediated immunoinflflammatory metabolic renal damage.

[Effects of Tengmei Decoction on the PPAR-y/NF-KB Signaling Pathway in Synovium of Collagen-in- duced Arthritis Rats].

Objective To observe the effects of Tengmei Decoction (TMD) on the expressions of peroxisome proliferator activated receptor gamma (PPARγ) , nuclear factor kappa B (NF-κB) , and IL- 17 in synovium of collagen-induced arthritis (CIA) rats, and to study its molecular mechanismpf. inhibi- ting synovial immune inflammatory injuries. Methods CIA model was established in Sprague-Dawley rats. Successfully modeled rats were randomly divided into the model group, the positive drug ,oup, high and low dose TMD groups, 6 in each group. Besides, a normal group was set up (n =6). Deionized water (10 mL . kg⁻¹ . d⁻¹) was administrated to rats in the normal group and the model group by gastro- gavage. Leflunomide (1. 87 mg . kg ⁻¹ . d ⁻¹) was administrated to rats in the positive drug group by gastro- gavage. TMD (31. 8 g crude drugs . kg ⁻¹ . d ⁻¹ and 15. 9 g crude drugs . kg ⁻¹ . d ⁻¹) was administrated to rats in high and low dose TMD groups respectively by gastrogavage. The intervention lasted for 12 suc- cessive weeks. Protein and mRNA levels of PPARy, P65, and IL-17 were detected at the end of intervention. Results Compared with the normal group, mRNA and protein expression levels of PPARγ, P65, and IL-17 were up-regulated in the model group (P <0. 01). Compared with the model group, PPARγ pro- tein expression level was up-regulated, mRNA and protein expression levels of P65 and IL-17 were down-regulated in high dose TMD group (P <0. 01). mRNA and protein expression levels of PPARγ were up-regulated, mRNA and protein expression levels of P65 and IL-17 were down-regulated in the positive drug group and low dose TMD group (P <0. 01). Conclusions TMD could ameliorate pathological damage of joint synovium , and inhibit expressions of immune inflammatory factors.