Evaluation of in vitro and in vivo anti-inflammatory effects of (-)-pseudosemiglabrin, a major phytoconstituent isolated from Tephrosia apollinea (Delile) DC.

ETHNOPHARMACOLOGICAL RELEVANCE: Tephrosia apollinea (Delile) DC (Leguminosae) has been used in folk medicine in Arabian countries to treat inflammatory disorders. The plant has been described to treat swelling, bone fracture, bronchitis, cough, earache and wounds. AIM OF THE STUDY: the current study aims to evaluate the anti-inflammatory properties of the major active phytoconstituent of T. apollinea and elucidate the mechanisms by which it inhibits inflammation in vitro and in vivo. MATERIAL AND METHODS: The compound, (-)-pseudosemiglabrin (SSG) was isolated as a major component from the aerial parts of T. apollinea using column chromatography techniques. Sub-chronic in vivo anti-inflammatory effect of SSG was assessed using cotton pellet granuloma assay in SD rats and serum levels of tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1) and nitric oxide (NO) were measured, whereas, tail flick assay was performed to assess the analgesic effect of SSG. Furthermore, the anti-inflammatory effects of SSG were confirmed by measuring the levels of IL-1, TNF-α, and NO in vitro using human macrophage cell lines (U937). In addition COX inhibition assay was also conducted in cells-free system. In silico study was performed to dock SSG in cyclooxygenase enzymes and opioid receptor to predict its structure-activity and molecular mechanism. RESULTS: SSG displayed potential inhibition of granuloma tissue in rats and significantly (P<0.05) lowered the production of cytokines (TNF- α and IL-1) in vivo as well as human macrophages. Further investigation revealed that, SSG selectively inhibited COX-2 by 60% with negligible effect on COX-1. The selectivity of SSG towards COX-2 was confirmed in silico wherein, SSG demonstrated significant binding affinity with binding energy (-9.42kcal/mol). The binding found to be through covalent energy with Ser-530 amino acid residue of the active pocket of COX-2. SSG was found to prolong the flick tail time in mice by two folds. Further computational studies reveal that SSG binds to opioid receptor (µ-OR) through Ile-144 and Thr-218 with affinity two folds compared to the reference compounds, codeine and aspirin. CONCLUSION: In the present study the major phytoconstituent (-)-pseudosemiglabrin (SSG) from the aerial parts of T. apollinea demonstrated potent anti-inflammatory effect by inhibiting of granuloma tissue in rats and prolonging the tail flick time in mice. Investigation of levels of pro-inflammatory cytokines in SSG-treated rats and human macrophages demonstrated that SSG significantly inhibited TNF-α and IL-1. Also SSG showed selective inhibitory effect towards COX-2. In silico study exhibited pronounced binding affinity between SSG and µ-opioid receptor better than that of codeine and aspirin. The obtained results justify the use of aerial parts of T. apollinea to treat various inflammatory diseases and indicate that (-)-pseudosemiglabrin has a great potential to be further developed as a promising anti-inflammatory drug.

Ethyl-p-methoxycinnamate isolated from Kaempferia galanga inhibits inflammation by suppressing interleukin-1, tumor necrosis factor-α, and angiogenesis by blocking endothelial functions.

OBJECTIVE: The present study aimed to investigate the mechanisms underlying the anti-inflammatory and anti-angiogenic effects of ethyl-p-methoxycinnamate isolated from Kaempferia galanga. METHODS: The anti-inflammatory effects of ethyl-p-methoxycinnamate were assessed using the cotton pellet granuloma assay in rats, whereby the levels of interleukin-1 and tumor necrosis factor-α were measured in the animals' blood. In addition, the levels of interleukin, tumor necrosis factor, and nitric oxide were measured in vitro using the human macrophage cell line (U937). The analgesic effects of ethyl-p-methoxycinnamate were assessed by the tail flick assay in rats. The anti-angiogenic effects were evaluated first by the rat aortic ring assay and, subsequently, by assessing the inhibitory effects of ethyl-p-methoxycinnamate on vascular endothelial growth factor, proliferation, migration, and tube formation in human umbilical vein endothelial cells. RESULTS: Ethyl-p-methoxycinnamate strongly inhibited granuloma tissue formation in rats. It prolonged the tail flick time in rats by more than two-fold compared with the control animals. The inhibition of interleukin and tumor necrosis factor by ethyl-p-methoxycinnamate was significant in both in vivo and in vitro models; however, only a moderate inhibition of nitric oxide was observed in macrophages. Furthermore, ethyl-p-methoxycinnamate considerably inhibited microvessel sprouting from the rat aorta. These mechanistic studies showed that ethyl-p-methoxycinnamate strongly inhibited the differentiation and migration of endothelial cells, which was further confirmed by the reduced level of vascular endothelial growth factor. CONCLUSION: Ethyl-p-methoxycinnamate exhibits significant anti-inflammatory potential by inhibiting pro-inflammatory cytokines and angiogenesis, thus inhibiting the main functions of endothelial cells. Thus, ethyl-p-methoxycinnamate could be a promising therapeutic agent for the treatment of inflammatory and angiogenesis-related diseases.

Ethyl-p-methoxycinnamate isolated from kaempferia galanga inhibits inflammation by suppressing interleukin-1, tumor necrosis factor-α, and angiogenesis by blocking endothelial functions

OBJECTIVE: The present study aimed to investigate the mechanisms underlying the anti-inflammatory and anti-angiogenic effects of ethyl-p-methoxycinnamate isolated from Kaempferia galanga. METHODS: The anti-inflammatory effects of ethyl-p-methoxycinnamate were assessed using the cotton pellet granuloma assay in rats, whereby the levels of interleukin-1 and tumor necrosis factor-α were measured in the animals' blood. In addition, the levels of interleukin, tumor necrosis factor, and nitric oxide were measured in vitro using the human macrophage cell line (U937). The analgesic effects of ethyl-p-methoxycinnamate were assessed by the tail flick assay in rats. The anti-angiogenic effects were evaluated first by the rat aortic ring assay and, subsequently, by assessing the inhibitory effects of ethyl-p-methoxycinnamate on vascular endothelial growth factor, proliferation, migration, and tube formation in human umbilical vein endothelial cells. RESULTS: Ethyl-p-methoxycinnamate strongly inhibited granuloma tissue formation in rats. It prolonged the tail flick time in rats by more than two-fold compared with the control animals. The inhibition of interleukin and tumor necrosis factor by ethyl-p-methoxycinnamate was significant in both in vivo and in vitro models; however, only a moderate inhibition of nitric oxide was observed in macrophages. Furthermore, ethyl-p-methoxycinnamate considerably inhibited microvessel sprouting from the rat aorta. These mechanistic studies showed that ethyl-p-methoxycinnamate strongly inhibited the differentiation and migration of endothelial cells, which was further confirmed by the reduced level of vascular endothelial growth factor. CONCLUSION: Ethyl-p-methoxycinnamate exhibits significant anti-inflammatory potential by inhibiting pro-inflammatory cytokines and angiogenesis, thus inhibiting the main functions of endothelial cells. Thus, ethyl-p-methoxycinnamate could be a promising therapeutic agent ...

Cucurbitacin L 2-O-ß-Glucoside Demonstrates Apoptogenesis in Colon Adenocarcinoma Cells (HT-29): Involvement of Reactive Oxygen and Nitrogen Species Regulation.

Emerging evidence suggests that reactive oxygen (ROS) and nitrogen (RNS) species can contribute to diverse signalling pathways of inflammatory and tumour cells. Cucurbitacins are a group of highly oxygenated triterpenes. Many plants used in folk medicine to treat cancer have been found to contain cucurbitacins displaying potentially important anti-inflammatory actions. The current study was designed to investigate the anti-ROS and -RNS effects of cucurbitacin L 2-O-ß-glucoside (CLG) and the role of these signaling factors in the apoptogenic effects of CLG on human colon cancer cells (HT-29). This natural cucurbitacin was isolated purely from Citrullus lanatus var. citroides (Cucurbitaceae). The results revealed that CLG was cytotoxic to HT-29. CLG increased significantly (P < 0.05) RNA and protein levels of caspase-3 in HT-29 cells when verified using a colorimetric assay and realtime qPCR, respectively. The results showed that lipopolysaccharide/interferon-gamma (LPS/INF-γ) increased nitrous oxide (NO) production inR AW264.7macrophages, whereas N(G)-nitro-L-argininemethyl ester (L-NAME) and CLG curtailed it. This compound did not reveal any cytotoxicity on RAW264.7 macrophages and human normal liver cells (WRL-68) when tested using the MTT assay. Findings of ferric reducing antioxidant power (FRAP) and oxygen radical absorption capacity (ORAC) assays demonstrate the antioxidant properties of CLG. The apoptogenic property of CLG on HT-29 cells is thus related to inhibition of reactive nitrogen and oxygen reactive species and the triggering of caspase-3-regulated apoptosis.

Anti-inflammatory activities of cucurbitacin E isolated from Citrullus lanatus var. citroides: role of reactive nitrogen species and cyclooxygenase enzyme inhibition.

The in vivo and in vitro mechanistic anti-inflammatory actions of cucurbitacin E (CE) (Citrullus lanatus var. citroides) were examined. The results showed that LPS/INF-γ increased NO production in RAW264.7 macrophages, whereas L-NAME and CE curtailed it. CE did not reveal any cytotoxicity on RAW264.7 and WRL-68 cells. CE inhibited both COX enzymes with more selectivity toward COX-2. Intraperitoneal injection of CE significantly suppressed carrageenan-induced rat's paw edema. ORAC and FRAP assays showed that CE is not a potent ROS scavenger. It could be concluded that CE is potentially useful in treating inflammation through the inhibition of COX and RNS but not ROS.