Ovatodiolide suppresses allergic airway inflammation and hyperresponsiveness in a murine model of asthma

N-methylpiperazine-diepoxyovatodiolide ameliorates peritoneal fibrosis via suppressing TGF-β/Smad and JAK/STAT signaling pathway

Peritoneal fibrosis (PF) is the main cause of peritoneal ultrafiltration failure in patients undergoing long-term peritoneal dialysis (PD). Epithelial-mesenchymal transition (EMT) is the key pathogenesis of PF. However, currently, no specific treatments are available to suppress PF. N-methylpiperazine-diepoxyovatodiolide (NMPDOva) is a newly synthesized compound that involves a chemical modification of ovatodiolide. In this study, we aimed to explore the antifibrotic effects of NMPDOva in PD-related PF and underlying mechanisms. A mouse model of PD-related PF was established via daily intraperitoneal injection of 4.25% glucose PD fluid. In vitro studies were performed using the transforming growth factor-beta1 (TGF-β1)-stimulated HMrSV5 cell line. Pathological changes were observed, and fibrotic markers were significantly elevated in the peritoneal membrane in mice model of PD-related PF. However, NMPDOva treatment significantly alleviated PD-related PF by decreasing the extracellular matrix accumulation. NMPDOva treatment decreased the expression of fibronectin, collagen Ⅰ, and alpha-smooth muscle actin (α-SMA) in mice with PD-related PF. Moreover, NMPDOva could alleviate TGF-β1-induced EMT in HMrSV5 cells, inhibited phosphorylation and nuclear translocation of Smad2/3, and increased the expression of Smad7. Meanwhile, NMPDOva inhibited phosphorylation of JAK2 and STAT3. Collectively, these results indicated that NMPDOva prevents PD-related PF by inhibiting the TGF-β1/Smad and JAK/STAT signaling pathway. Therefore, because of these antifibrotic effects, NMPDOva may be a promising therapeutic agent for PD-related PF.

Ovatodiolide protects ischemia-reperfusion-induced neuronal injury via microglial neuroinflammation via mediating SIRT1/NF-κB pathway

BACKGROUND

Ovatodiolide (OVA), a bioactive substance extracted from the bioactive component of Anisomeles indica, is reported to be endowed with anti-inflammatory properties. Nonetheless, its function in ischemia-reperfusion (I/R)-induced neurological deficits and microglial inflammation remains unclear.

METHOD

A middle cerebral artery occlusion (MCAO) model was set up in SD rats, which were then dealt with varying doses of OVA. The rats' neurological functions were estimated at diverse periods postoperatively. The dry and wet method, triphenyl tetrazolium chloride (TTC) staining, and Nissl's staining were conducted to measure brain edema, cerebral infarction area and neuronal damage, respectively. Immunohistochemistry (IHC) was performed to detect neuronal apoptosis and microglial activation, and the profiles of inflammatory factors in the cerebral tissues were estimated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). In-vitro assays were implemented on HT22 neuronal cells and BV2 microglia to elaborate the effect of OVA against oxygen-glucose deprivation (OGD)-mediated effects.

RESULTS

OVA relieved HT22 cell apoptosis and eased inflammation in BV2 microglia, which were induced by OGD. OVA mitigated NF-κB phosphorylation in BV2 cells, whereas boosted SIRT1 expression. However, inhibiting SIRT1 abolished the anti-inflammatory effects of OVA in BV2 microglia under OGD stimulation. The condition medium (CM) of OGD-treated BV2 cells enhanced HT22 cell apoptosis and damage. OVA treatment in BV2 cells relieved BV2-mediated injury on HT22 cells, which was reversed by SIRT1 inhibitor. In-vivo results revealed that OVA dose-dependently attenuated I/R rats' neurological deficits, reduced brain edema, cerebral infarction area, neuronal apoptosis and microglial overactivation. Additionally, OVA inactivated the NF-κB pathway and up-regulated SIRT1 in the I/R rat model.

CONCLUSION

OVA prevented rats from brain I/R damage by hampering neuronal apoptosis and microglial inflammation via the SIRT1-NF-κB pathway.

DATA AVAILABILITY

The data sets used and analyzed during the current study are available from the corresponding author on reasonable request.

Innovative Purification Method of Ovatodiolide from Anisomeles indica to Induce Apoptosis in Human Gastric Cancer Cells

Ovatodiolide (Ova), found in the plant Anisomeles indica (AI), has been reported to have an anti-proliferation effect in various cancer cells. However, little information is available regarding the anti-cancer effect of Ova in human gastric cancer cells. In this study, we investigated the inhibitory effects and the mechanisms of action responsible for these effects on human AGS cell lines from a newly developed purification technique for Ova from AI extract. Extract obtained at the optimum condition of 95% ethanol extraction of AI was sequentially partitioned by using different polarity solvents. Enriched content of Ova (35.9% purity) from the n-hexane fraction was then applied to the purification by using centrifugal partition chromatography (CPC) in a two-phase solvent system consisting of n-hexane:ethyl acetate:methanol:water (1.0:1.0:1.0:1.0, v/v/v/v) to reach purity over >95.0%. In evaluation of the anti-proliferation effect on AGS cells, Ova induced cell apoptosis with IC₅₀ values of 13.02 and 6.18 μM at 24 and 48 h, respectively, and arrested the cells at the G2/M phase. Quantification of Bax/Bcl2 mRNA expressions using qPCR showed a 2.5-fold increase in the Ova (5 μM)-treated cells at 48 h than in the control group. Specific protein expression data warrant further research to further confirm the proposed Ova-induced apoptotic pathway in AGS cells.

Genotoxicity and 28-day repeated dose oral toxicity study of ovatodiolide in rats

Ovatodiolide is a bioactive cembrane-type diterpenoid isolated from Anisomeles indica (L.) Kuntze. It has been proven that ovatodiolide is anti-inflammatory, anti-tumorigenic, anti-melanogenic and attenuates asthma by regulating signaling pathways. The aim of this study was to evaluate the safety of ovatodiolide by conducting genotoxicity tests and 28-day oral toxicity tests in rats. Genotoxicity assays were conducted by using a bacterial reverse mutation test and mammalian chromosomal aberration test to assess whether ovatodiolide causes reverse mutations and mutagenicity with or without metabolism activation. For the in vivo mammalian erythrocyte micronucleus test, mice were administered a single dose of 0, 250, 500 or 1000 mg/kg b.w. ovatodiolide by single gavage. In the acute oral toxicity test, rats were given a single dose of ovatodiolide 1000 mg/kg b.w. by single gavage. In the 28-day oral toxicity test, groups were divided into a control, ovatodiolide 10, 25 and 50 mg/kg b.w. The results showed that there was no mutagenicity in the bacterial reverse mutation test or the mammalian chromosomal aberration test with or without S9 fraction. Ovatodiolide did not produce an increase in micronucleated reticulocytes in the micronucleus test. The results revealed that the acute oral toxicity of ovatodiolide is over 1000 mg/kg b.w. in rats. Moreover, 10, 25 and 50 mg/kg b.w. of ovatodiolide did not cause a significant effect in rats. According to the results of the genotoxicity and oral toxicity studies in rats, ovatodiolide did not produce any adverse effects, and the tested doses can serve as clinical references.

Ovatodiolide suppresses inflammatory response in BEAS-2B cells by regulating the CREB/AQP5 pathway, and sensitizes nasopharyngeal carcinoma cells to radiation therapy

Due to the radiosensitivity of the airway epithelium, radiation-induced sinusitis or bronchitis is not uncommon, and makes mitigation of resulting inflammatory airway diseases a principal goal of many investigations. This study examined whether Ovatodiolide (Ova) sensitizes the human metastatic nasopharyngeal cancer (NPC) cell line, NPC-BM2, to irradiation using viability, clonogenicity and Western blot assays. Concurrently, we used varying concentrations of histamine and/or Ova to determine the anti-inflammatory potential of Ovatodiolide on normal bronchus epithelial BEAS-2B cells, as well as on the subcellular distribution of Aquaporin 5 (AQP5) and expression levels of p-CREB, AQP5, p38 MAPK, NF-κB, PI3K, Akt and ERK proteins. We demonstrated that Ova in synergism with irradiation inhibited NPC-BM2 cell viability and suppressed their clonogenicity. Immunofluorescence analysis revealed low-dose (≤ 2.5 μM) Ova reversed histamine-induced suppression of AQP5 expression, and abrogated histamine-enhanced NF-κB nuclear translocation, indicating Ova modulates the p38 MAPK/NF-κB signaling pathway and elicits p-CREB/AQP5-mediated antihistamine effects. Similarly, Ova deregulates the PI3K/Akt/ERK signaling in BEAS-2B cells, suggesting its cytoprotective potential. In conclusion, this study highlights the radio-sensitizing anticancer efficacy of Ova in human metastatic NPC cells, as well as its putative cytoprotective role in normal bronchial cells, for airway surface liquid maintenance and homeostasis during or after radiotherapy.