A comparative investigation of the interaction and pharmacokinetics of hemoglobin with berberine and its oxymetabolite.

Berberine (BBR), isolated from Coptis chinensis, is one type of isoquinoline alkaloids. BBR exerts numerous of bioactivities but the plasma concentration is really low. In our previous study, a new oxymetabolite (OBB) has been discovered and showed superior anti-inflammatory effect comparing with BBR. The aim of this study is to investigate the interaction, metabolite and pharmacokinetics of BBR with hemoglobin. Sprague-Dawley rats were used to carry out the interaction, metabolite and pharmacokinetics of BBR and OBB in vivo. Fluorescence spectra were used to analyse the interaction in vitro. Results showed that OBB could be generated after intravenous injection or incubating with BBR in vitro and in vivo; Both BBR and OBB exerted much stronger binding interaction with hemoglobin than plasma and affect the conformation of bovine hemoglobin and change the fluorescence spectral properties; BBR and OBB were mainly presented and transported in the proteins-bound form. These results provide a new insight to understand the dynamic equilibrium of BBR and OBB within body from the perspective of new metabolic pathways.

Comparison of anti-inflammatory effects of berberine, and its natural oxidative and reduced derivatives from Rhizoma Coptidis in vitro and in vivo.

BACKGROUND: Berberine (BBR) is the most abundant and major active constituent of Rhizoma Coptidis (RC), which has been widely used to treat inflammatory diseases in traditional oriental medicine. Despite BBR has been found to exhibit pronounced anti-inflammatory effect, the anti-inflammatory activities of its natural derivatives were sparsely dissected out. PURPOSE: To comparatively investigate the anti-inflammatory potential of BBR, and its natural oxoderivative (oxyberberine, OBB) and reduced derivative (dihydroberberine, DHBB) in vitro and in vivo, and delineate the possible underlying mechanism. METHODS: LC-MS/MS was used to identify the natural derivatives of BBR in RC. The potential anti-inflammatory properties of BBR and its natural derivatives were comparatively evaluated in vitro by lipopolysaccharide (LPS)-induced RAW264.7 macrophages cells, and in vivo via three typical acute inflammation murine models. Some important inflammation-related molecules were analyzed by ELISA, qRT-PCR and Western blotting. RESULTS: LC-MS/MS led to the identification of BBR, OBB and DHBB in RC ethyl acetate extract. The in vitro assay indicated that BBR, OBB and DHBB (1.25, 2.5 and 5 µM) pretreatment significantly decreased the levels of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6), prostaglandinE2 (PGE2) and nitricoxide (NO), and inhibited the mRNA expressions of cyclooxygenase-2 (COX-2) and inducible nitricoxide synthase (iNOS) in a dose-dependent manner, with relative efficiency of OBB > BBR > DHBB. Furthermore, OBB, BBR and DHBB remarkably inhibited the phosphorylation of nuclear factor-κB (NF-κB) p65 and inhibitory kappa Bα (IκBα). In vivo, BBR (20 mg/kg) and OBB (5, 10, and 20 mg/kg) pretreatment significantly ameliorated the xylene-induced ear edema, carrageenan-stimulated paw edema, and acetic acid-elicited vascular permeability in mice in a dose-dependent manner, with OBB exhibiting superior anti-inflammatory effect at the same dose (20 mg/kg). Histopathological analysis indicated that OBB and BBR could markedly attenuate the inflammatory deterioration and decrease the cellular infiltration in paw tissues. Additionally, the carrageenan-induced increases in TNF-α, IL-6, IL-1ß, PGE2 and NO productions, and COX-2 and iNOS mRNA expressions were effectually and concentration-dependently suppressed by OBB and BBR pretreatment. CONCLUSION: The anti-inflammatory activity of BBR and its natural derivatives was in the order of OBB > BBR > DHBB. OBB was for the first time found to be endowed with pronounced anti-inflammatory property, which was probably associated with suppressing the activation of NF-κB signaling pathway, and the subsequent gene expressions and productions of pro-inflammatory mediators. The results might contribute to illuminating the pharmacodynamic underpinnings of RC and provide evidence for developing OBB as a safe and promising natural lead compound in inflammation treatment.

Anti-inflammatory activity of coptisine free base in mice through inhibition of NF-κB and MAPK signaling pathways.

Coptisine is one of the main constituents of Coptis chinensis which has been widely used for the remedy of inflammatory disorders. Although the biological activities of coptisine have been well known, the pharmacological properties of its free base have seldomly been elucidated thus far. The aim of this study was to investigate the potential anti-inflammatory properties of coptisine free base (CFB, 8-hydroxy-7,8-dihydrocoptisine) on three animal models, namely xylene-induced ear edema, acetic acid-induced vascular permeability and carrageenan-induced paw edema. The results exhibited that CFB exerted a dose-dependent suppression on ear edema induced by xylene, significantly mitigated the aggravation of vascular permeability caused by acetic acid and paw edema induced by carrageenan. Additionally, CFB significantly suppressed the productions of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), prostaglandinE2 (PGE2) and tumor necrosis factor (TNF-α) in the drug-treated groups as compared with the vehicle group after treatment with carrageenan. Signaling events of nuclear factor-κB (NF-κB) translocation, such as p-IKKα, p-IKKß, p-IκBα and p65 (nucleus) were significantly inactivated, while inhibitor of nuclear factor κBα (IκBα) and p65 (cytosolic) were markedly up-regulated by CFB. Furthermore, CFB also significantly suppressed the mitogen-activated protein kinase (MAPK) pathway by blocking the phosphorylation of p-p38 (phospho-p38 mitogen-activated protein kinases) and p-JNK (phospho-c-jun N-terminal kinase) but not p-ERK (phospho-extracellular signal-regulated kinase). Hence, CFB efficiently prevented inflammation, at least partially, via inhibition of NF-κB and MAPK pathways. These findings provided a pioneering pharmacological basis for the anti-inflammatory effect of CFB and suggested CFB might be a potential candidate for the therapy of inflammatory disorders.