Cellular and Molecular Mechanisms and Effects of Berberine on Obesity-Induced Inflammation.

Obesity represents chronic low-grade inflammation that precipitates type 2 diabetes, cardiovascular disease, and cancer. Berberine (BBR) has been reported to exert anti-obesity and anti-inflammatory benefits. We aimed to demonstrate the underlying immune-modulating mechanisms of anti-obesity effects of BBR. First, we performed in silico study to identify therapeutic targets, describe potential pathways, and simulate BBR docking at M1 and M2 adipose tissue macrophages (ATMs), tumor necrosis factor-α (TNF-α), C-C motif chemokine ligand 2 (CCL2), CCL4, CCL5, and C-X-C motif chemokine receptor 4 (CXCR4). Next, in vivo, we divided 20 C58BL/6 mice into four groups: normal chow, control (high fat diet (HFD)), HFD + BBR 100 mg/kg, and HFD + metformin (MET) 200 mg/kg. We evaluated body weight, organ weight, fat area in tissues, oral glucose and fat tolerance tests, HOMA-IR, serum lipids levels, population changes in ATMs, M1 and M2 subsets, and gene expression of TNF-α, CCL2, CCL3, CCL5, and CXCR4. BBR significantly reduced body weight, adipocyte size, fat deposition in the liver, HOMA-IR, triglycerides, free fatty acids, ATM infiltration, all assessed gene expression, and enhanced the CD206+ M2 ATMs population. In conclusion, BBR treats obesity and its associated metabolic dysfunctions, by modulating ATM recruitment and polarization via chemotaxis inhibition.

Puerarin Attenuates Obesity-Induced Inflammation and Dyslipidemia by Regulating Macrophages and TNF-Alpha in Obese Mice.

Obesity causes low-grade inflammation that results in dyslipidemia and insulin resistance. We evaluated the effect of puerarin on obesity and metabolic complications both in silico and in vivo and investigated the underlying immunological mechanisms. Twenty C57BL/6 mice were divided into four groups: normal chow, control (HFD), HFD + puerarin (PUE) 200 mg/kg, and HFD + atorvastatin (ATO) 10 mg/kg groups. We examined bodyweight, oral glucose tolerance test, serum insulin, oral fat tolerance test, serum lipids, and adipocyte size. We also analyzed the percentage of total, M1, and M2 adipose tissue macrophages (ATMs) and the expression of F4/80, tumor necrosis factor-α (TNF-α), C-C motif chemokine ligand 2 (CCL2), CCL4, CCL5, and C-X-C motif chemokine receptor 4. In silico, we identified the treatment-targeted genes of puerarin and simulated molecular docking with puerarin and TNF, M1, and M2 macrophages based on functionally enriched pathways. Puerarin did not significantly change bodyweight but significantly improved fat pad weight, adipocyte size, fat area in the liver, free fatty acids, triglycerides, total cholesterol, and HDL-cholesterol in vivo. In addition, puerarin significantly decreased the ATM population and TNF-α expression. Therefore, puerarin is a potential anti-obesity treatment based on its anti-inflammatory effects in adipose tissue.

Ethanol extract of Prunella vulgaris var. lilacina inhibits HMGB1 release by induction of heme oxygenase-1 in LPS-activated RAW 264.7 cells and CLP-induced septic mice.

The ethanol extract of the flower of P. vulgaris var. lilacina (EEPV) has been used traditionally as an antiinflammatory agent in many countries. Inducers of heme oxygenase-1 (HO-1) reduce high mobility group box 1 (HMGB1), a late phase cytokine, in sepsis. Although EEPV has been used as an antiinflammatory agent, no report is available as to whether it modifies HMGB1 in sepsis due to HO-1 induction. It was found that EEPV increased HO-1 protein expression in RAW 264.7 cells, which was significantly inhibited by LY294002, but not PD98059, SB203580 or SP600125. In addition, EEPV activated NF-E2-related factor (Nrf2) to move from the cytosol to the nucleus, and EEPV-induced HO-1 and activation of ARE-luciferase activity were significantly reduced by siNrf2 transfection and LY294002 but not SB203508. EEPV also significantly inhibited NF-κB luciferase activity, and decreased both iNOS/NO and COX-2/PGE(2) production in lipopolysaccharide (LPS)-stimulated macrophages which was reversed by siHO-1 RNA transfection. Importantly, EEPV inhibited HMGB1 release in LPS-activated macrophages in a PI3K-sensitive manner and reduced serum HMGB1 level and lung HMGB1 expression in cecal ligation and puncture (CLP)-induced septic mice. It is concluded that EEPV induces HO-1 expression through PI3K/Nrf2 signal pathways, which may be beneficial for the treatment of sepsis due to a reduction of HMGB1 release.

Isoimperatorin, cimiside E and 23-O-acetylshengmanol-3-xyloside from Cimicifugae rhizome inhibit TNF-α-induced VCAM-1 expression in human endothelial cells: involvement of PPAR-γ upregulation and PI3K, ERK1/2, and PKC signal pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: The methanol extract of Cimicifugae Rhizome has been traditionally used in various disorders including inflammation. AIM OF THE STUDY: The aim of the study is to explore whether anti-inflammatory action of 3 active compounds, two triterpenoid glycosides (cimiside E, 23-O-actylshengmanol-3-xyloside) and one furanocoumarin (isoimperatorin), isolated from Cimicifugae Rhizome is related with peroxisome proliferator-activated receptor-γ (PPAR-γ) expression in human umbilical endothelial cell line, EA.hy926 cells. MATERIALS AND METHODS: Cell viability and production of reactive oxygen species were performed. In addition, adhesion of monocyte into endothelial cells and western blot for expression of adhesion molecules and signal proteins were investigated in tumor necrosis factor-α (TNF-α)-activated cells. RESULTS: Pretreatment of test compounds significantly reduced reactive oxygen species (ROS) production and expression of vascular cell adhesion molecule-1 (VCAM-1), but not intercellular cell adhesion molecule-1 (ICAM-1). Three compounds all dose-dependently increased not only PPAR-γ expression in EA.hy926 cells but inhibited TNF-α-induced phosphorylation of Akt, extracellular-signal-regulated kinase (ERK) and protein kinase C (PKC) with different specificity. Finally, they prevented TNF-α-induced adhesion of U937 monocytic cells to EA.hy926 cells. CONCLUSIONS: The present results show that cimiside E, 23-O-actylshengmanol-3-xyloside, isoimperatorin isolated from Cimicifugae Rhizome selectively inhibits TNF-α-induced expression of VCAM-1 at least by upregulation of PPAR-γ, and signals for ERK1/2, PI3K, and PKC are involved in this effect.

7,8-didehydrocimigenol from Cimicifugae rhizoma inhibits TNF-α-induced VCAM-1 but not ICAM-1expression through upregulation of PPAR-γ in human endothelial cells.

Activators of PPAR have been demonstrated to inhibit the induction of VCAM-1 but not ICAM-1 in human endothelial cells (EC). During the screening of anti-inflammatory activity of traditional herbs, we found 7,8-didehydrocimigenol (7,8-DHC), one of active triterpenoids of Cimicifugae rhizoma (C. rhizoma) increases PPAR-γ expression in EC in a time- and dose-dependent manner. Therefore, we asked whether 7,8-DHC selectively inhibits the expression of VCAM-1 but not ICAM-1 in TNF-α-activated EC via upregulation of PPAR-γ. Treatment with 7,8-DHC or PPAR-γ agonists (GW1929, troglitazone) inhibited the expression of VCAM-1 but not ICAM-1. Furthermore, the selective inhibition of VCAM-1 expression was inhibited by PPAR-γ antagonist, GW9662, or siPPAR-γ-transfected cells. 7,8-DHC significantly inhibited NF-kB activity via inhibition of phosphorylation of IkB and it also inhibited phosphorylation of ERK1/2 and Akt but not PKC. Finally, attachment of monocytes (U937) to EC by TNF-α was significantly reduced by 7,8-DHC. These results indicate that upregualtion of PPAR-γ by 7,8-DHC in EC inhibits NF-kB activity of TNF-α-activated EC which leads to selective inhibition of VCAM-1 expression. In addition, ERK1/2 and Akt signal pathways are involved in differential regulation by 7,8-DHC. We concluded that 7,8-DHC can be used for the treatment of cardiovascular disorders such as atherosclerosis.

Anti-inflammatory action of methanol extract of Carthamus tinctorius involves in heme oxygenase-1 induction.

ETHNOPHARMACOLOGICAL RELEVANCE: The methanol extracts of Carthamus tinctorius (MEC) have long been used in traditional medicine as anti-inflammatory agent, however, the molecular mechanism by which MEC shows anti-inflammatory action is not investigated. AIM OF THE STUDY: Induction of heme oxygenase-1 (HO-1) by many medicinal herbs has been reported excellent anti-inflammatory action. Thus, the aim of the study is to explore whether anti-inflammatory action of MEC is related with HO-1 induction in RAW 264.7 cells. MATERIALS AND METHODS: The present study was designed to investigate as to MEC induces HO-1 expression so that it reduces inflammation by suppression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression in cells activated with lipopolysaccharide (LPS). RESULTS: Expression of HO-1 protein by MEC in macrophages was increased in a concentration- and time-dependent manner. Treatment with MEC significantly inhibited upregulation of both iNOS and COX-2 in LPS-activated macrophages and consequently reduced production of NO and PGE(2), respectively. The reduced expression of iNOS and COX-2 by MEC was reversed by siHO-1 RNA transfection. In addition, NF-E2-related factor (Nrf2) was translocated from cytosol to nucleus by MEC. The binding of NF-κB as well as NF-κB luciferase activity was also significantly diminished by MEC. Finally, tumor necrosis factor (TNF)-α-mediated VCAM-1 expression in endothelial cell was significantly inhibited by MEC. CONCLUSIONS: The present results show that MEC induces HO-1 expression via Nrf2 translocation and inhibits NF-κB activity, which may be responsible for anti-inflammatory action. Therefore, we propose that anti-inflammatory action of MEC involves at least HO-1 induction.