Rehmannia glutinosa Suppresses Inflammatory Responses Elicited by Advanced Glycation End Products

Abstract

Fresh rhizome of Rehmannia glutinosa Libosch. (Saeng-jihwang in Korean: SJH) has been prescribed for the treatment of diabetes-associated complications. The purpose of the present study is to investigate the underlying mechanisms of the efficacy of SJH in diabetes-related complications. Decoction was obtained after boiling SJH in water and subsequent lyophilization. The cellular toxicity of SJH was determined by MTT assay. The antioxidant activity of SJH was measured by DPPH and DCFH-DA assays. The effects of SJH on inflammatory responses elicited by AGEs were assessed by western blotting and semi-quantitative RT-PCR analyses. The water extract of SJH had a high free radical scavenging activity in vitro and decreased the level of intracellular ROS in THP-1 cells treated with AGEs. SJH suppressed the expression of pro-inflammatory genes, including TNF-α, MCP-1, IP-10, COX-2, and iNOS; the activation of NF-κB; and the expression of RAGE, a receptor for AGEs, where the expressions of which were induced by AGEs. These results suggest the possibility that SJH can be an alternative therapeutics for diabetes-associated diseases.

Bioassay-guided isolation of anti-inflammatory components from the root of Rehmannia glutinosa and its underlying mechanism via inhibition of iNOS pathway

“…Moreover, our results were supported by the traditional usages of RR in alleviating inflammation, as well as the accumulating results of the evidence-based scientific experiments in inflammation area of RR (Kubo et al, 1994;Yu et al, 2006;Liu et al, 2007;Waisundara et al, 2008;Lau et al, 2009Lau et al, , 2012Sung et al, 2011;Baek et al, 2012). In particular, a recent study used human acute monocytic leukemia cell line for the investigation of antiinflammatory effect of RR aqueous crude extract upon the stimulation of advanced glycation end products (Baek et al, 2012).…”

“…In particular, a recent study used human acute monocytic leukemia cell line for the investigation of antiinflammatory effect of RR aqueous crude extract upon the stimulation of advanced glycation end products (Baek et al, 2012). The extract that they used was from another subtype of RR, known as fresh RR, different from our dried RR in their processing method and traditional uses.…”

“…Recently, we also revealed that the RR crude extract could significantly and dose-dependently inhibit nitric oxide production (Lau et al, 2012). Indeed, RR crude extract have also been reported to inhibit inflammatory responses in vitro triggered by advanced glycation end products (Baek et al, 2012) and protected against cell damage via scavenging free radicals (Yu et al, 2006). It inhibited inflammation via the reduction of plasma C-reactive protein in diabetic rats (Waisundara et al, 2008), in the development of atopic dermatitis (Sung et al, 2011), and in a rat lung inflammation model (Liu et al, 2007).…”

BDNF and COX-2 participate in anti-depressive mechanisms of catalpol in rats undergoing chronic unpredictable mild stress

“…Catalpol significantly reduced the activities and mRNA expression of COX-2 and PGE 2 levels in the two key brain regions. In fact, the COX-2 inhibitory effect of R. glutinosa or catalpol had been reported in previous studies [40,71,72]. For example, rehmapicrogenin-containing subfraction C3 from R. glutinosa exhibited potent anti-inflammatory effect by inhibiting COX-2 and PGE 2 [72].…”

Protection Against Electroshock- and Pentylenetetrazol-induced Seizures by the Water Extract ofRehmannia glutinouscan be Mediated through GABA Receptor-chloride Channel Complexes

“…[13][14][15][16][17][18][19][20] Despite its various biological benefits, the anticonvulsive activity of RG has not been evaluated. Thus, the aim of the present study was to evaluate the anticonvulsive effects of RG.…”