Cardioprotective effects of alantolactone on isoproterenol-induced cardiac injury and cobalt chloride-induced cardiomyocyte injury.

OBJECTIVES: Alantolactone (AL) is a compound extracted from the roots of Inula Racemosa that has shown beneficial effects in cardiovascular disease. However, the cardioprotective mechanism of AL against hypoxic/ischemic (H/I) injury is still unclear. This research aimed to determine AL's ability to protect the heart against isoproterenol (ISO)-induced MI injury in vivo and cobalt chloride (CoCl2) induced H/I injury in vitro. METHODS: Electrocardiography (ECG), lactate dehydrogenase (LDH), creatine kinase (CK), and cardiac troponin I (cTnI) assays in addition to histological analysis of the myocardium were used to investigate the effects of AL in vivo. Influences of AL on L-type Ca2+ current (ICa-L) in isolated rat myocytes were observed by the patch-clamp technique. Furthermore, cell viability, apoptosis, oxidative stress injury, mitochondrial membrane potential, and intracellular Ca2+ concentration were examined in vitro. RESULTS: The results indicated that AL treatment ameliorated the morphological and ECG changes associated with MI, and decreased levels of LDH, CK, and cTnI. Furthermore, pretreatment with AL elevated antioxidant enzyme activity and suppressed ROS production. AL prevented H/I-induced apoptosis, mitochondria damage, and calcium overload while reducing ICa-L in a concentration and time dependent fashion. The 50% inhibiting concentration (IC50) and maximal inhibitory effect (Emax) of AL were 17.29 µmol/L and 57.73 ± 1.05%, respectively. CONCLUSION: AL attenuated MI-related injury by reducing oxidative stress, apoptosis, calcium overload, and mitochondria damage. These cardioprotective effects may be related to the direct inhibition of ICa-L.

1,10-Seco-Eudesmane sesquiterpenoids as a new type of anti-neuroinflammatory agents by suppressing TLR4/NF-κB/MAPK pathways.

Dysregulation of neuroinflammation is a key pathological factor in the progressive neuronal damage of neurodegenerative diseases. An in-house natural products library of 1407 compounds were screened against neuroinflammation in lipopolysaccharide (LPS)-activated microglia cells to identify a novel hit 1,6-O,O-diacetylbritannilactone (OABL) with anti-neuroinflammatory activity. Furthermore, a 1,10-seco-eudesmane sesquiterpenoid library containing 33 compounds was constructed by semisynthesis of a major component 1-O-acetylbritannilactone (ABL) from the traditional Chinese medicinal herb Inula Britannica L. Compound 15 was identified as a promising anti-neuroinflammatory agent by nitrite oxide (NO) production screening. 15 could attenuate tumor necrosis factor-α (TNF-α) and prostaglandin E2 (PGE2) productions, and inhibit the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at a submicromolar level. Mechanistic study revealed that 15 significantly modulated TLR4/NF-kB and p38 MAPK pathways, and upregulated the anti-oxidant response HO-1. Besides, 15 promoted the conversion of the microglia from M1 to M2 phenotype by increasing levels of arginase-1 and IL-10. The structure-activity relationships (SARs) analysis indicated that the α-methylene-γ-lactone motifs, epoxidation of C5=C10 bond and bromination of C14 were important to the activity. Parallel artificial membrane permeation assay (PAMPA) also demonstrated that 15 and OABL can overcome the blood-brain barrier (BBB). In all, compound 15 is a promising anti-neuroinflammatory lead with potent anti-inflammatory effects via the blockage of TLR4/NF-κB/MAPK pathways, favorable BBB penetration property, and low cytotoxicity.

Therapeutic potential and pharmacological activities of ß-eudesmol.

Herbal medicines are attracting the attention of researchers worldwide. ß-Eudesmol is one of the most studied and major bioactive sesquiterpenes, mainly extracted from Atractylodes lancea (Thunb) DC. rhizomes. It has potential anti-tumor and anti-angiogenic activities and is an inhibitor of tumor growth by inhibiting angiogenesis by suppressing CREB activation of the growth factor signaling pathway. It also stimulates neurite outgrowth in rat pheochromocytoma cells with activation of mitogen-activated protein kinases. It may be a promising lead compound for enhancing neural function, and it may help to explain the underlying mechanisms of neural differentiation. In this review, we summarized the currently available clinical and preclinical studies describing the therapeutic applications of ß-eudesmol.

Alantolactone mitigates renal injury induced by diabetes via inhibition of high glucose-mediated inflammatory response and macrophage infiltration.

Background: Inflammatory response plays a crucial role in the occurrence and development of diabetic nephropathy (DN). Drugs that carry anti-inflammatory effects have the potential to treat diabetic nephropathy. It's reported that alantolactone (ALA), a natural product, has a variety of pharmacological effects against inflammation and oxidation. However, the specific effects of alantolactone on DN and the mechanisms underlying alantolactone remain elusive. Therefore, the present study aimed to probe whether ALA could mitigate inflammation as mediated by high glucose (HG) in NRK-52E cells and reduce renal injury caused by diabetic nephropathy.Materials and methods: The anti-inflammatory effect of ALA was evaluated in the present study using ELISA and RT-qPCR. Western blot and macrophage adhesion assay were then performed to confirm anti-macrophage adhesion and the protein expression of cell adhesion molecules. Finally, the effect of ALA and its underlying mechanism was evaluated in vivo.Results: Results showed that ALA curbed HG-stimulated expression of macrophage adhesion and pro-inflammatory cytokines in renal NRK-52E cells. In addition, both pro-inflammatory cytokines and NF-kappa B witnessed reduced expression or activity in oral administration with ALA in vivo, thus inhibiting the increase of serum creatinine and urea nitrogen (BUN) levels. This in consequence ameliorated fibrosis and stemmed pathological worsening of diabetic renal tissues.Conclusions: These findings suggest that ALA may hold promise in the treatment of DN, and importantly, the anti-inflammatory system may prove to be a new strategy to treat human DN.

Activation of PXR by alantolactone ameliorates DSS-induced experimental colitis via suppressing NF-κB signaling pathway.

Alantolactone (ALA) is a sesquiterpene lactone with potent anti-inflammatory activity. However, the effect of ALA on intestinal inflammation remains largely unknown. The present study demonstrated that ALA significantly ameliorated the clinical symptoms of dextran sulfate sodium (DSS)-induced mice colitis as determined by body weight loss, diarrhea, colon shortening, inflammatory infiltration and histological injury. In mice exposed to DSS, ALA treatment significantly lowered pro-inflammatory mediators, including nuclear factor-kappa B (NF-κB) activation. In vitro, ALA inhibited NF-κB nuclear translocation and dose-dependently activated human/mouse pregnane X receptor (PXR), a key regulator gene in inflammatory bowel disease (IBD) pathogenesis. However, the pocket occluding mutants of the ligand-binding domain (LBD) of hPXR, abrogated ALA-mediated activation of the receptor. Overexpression of hPXR inhibited NF-κB-reporter activity and in this setting, ALA further enhanced the hPXR-mediated inhibition of NF-κB-reporter activity. Furthermore, silencing hPXR gene demonstrated the necessity for hPXR in downregulation of NF-κB activation by ALA. Finally, molecular docking studies confirmed the binding affinity between hPXR-LBD and ALA. Collectively, the current study indicates a beneficial effect of ALA on experimental IBD possibly via PXR-mediated suppression of the NF-κB inflammatory signaling.

Alantolactone improves palmitate-induced glucose intolerance and inflammation in both lean and obese states in vitro: Adipocyte and adipocyte-macrophage co-culture system.

Obesity is characterized by a massive infiltration of the adipose tissue by macrophages. Adipocytes, together with macrophages create a crosstalk between inflammation and insulin resistance. Excess saturated FFA, such as palmitate, absorbed via the portal system may cause glucose intolerance and inflammation, which leads to insulin resistance. In this study, we aimed to evaluate the potency of alantolactone (AL), a sesquiterpene lactone isolated from Inula helenium in reducing palmitate-induced glucose intolerance, fat accumulation, and inflammation in 3T3-L1 adipocytes and adipocyte-macrophage co-culture system (3T3-L1-RAW264.7). We observed that palmitate reduced glucose uptake and increased fat accumulation, which indicated dysfunctional adipocytes with inadequate lipid storage. However, AL treatment reversed these changes in a dose-dependent manner (P<0.05). Palmitate activated c-Jun N-terminal kinases (JNK) and IκB kinase ß/α (IKKß/α) phosphorylation, and increased the levels of the proinflammatory cytokines (tumor necrosis factor-α and interleukin-6 [IL-6]) and chemokines (monocyte chemoattractant protein-1 [MCP-1]). AL treatment selectively reduced JNK-associated mitogen-activated protein kinase pathway (JNK and extracellular signal-regulated kinase phosphorylation). However, it did not affect NF-κB pathway in adipocytes. In addition, AL decreased the gene expression of JNK upregulating factor, toll-like receptor-4 (TLR4), suggesting inhibition of TLR4-JNK signaling. Moreover, it reduced inflammation-associated IL-6 and MCP-1 mRNA levels in both adipocytes and adipocyte-macrophage system. Our study showed that palmitate treatment led to adipocyte dysfunction and macrophage infiltration; however, AL improved palmitate-induced glucose intolerance and inflammation. These findings suggest that AL may inhibit obesity-induced insulin resistance and improve glucose homeostasis and inflammation in insulin target tissues.

Targeting apoptosis pathways in cancer with alantolactone and isoalantolactone.

Alantolactone and isoalantolactone, main bioactive compounds that are present in many medicinal plants such as Inula helenium, L. Inula japonica, Aucklandia lappa, Inula racemosa, and Radix inulae, have been found to have various pharmacological actions including anti-inflammatory, antimicrobial, and anticancer properties, with no significant toxicity. Recently, the anticancer activity of alantolactone and isoalantolactone has been extensively investigated. Here, our aim is to review their natural sources and their anticancer activity with specific emphasis on mechanism of actions, by which these compounds act on apoptosis pathways. Based on the literature and also on our previous results, alantolactone and isoalantolactone induce apoptosis by targeting multiple cellular signaling pathways that are frequently deregulated in cancers and suggest that their simultaneous targeting by these compounds could result in efficacious and selective killing of cancer cells. This review suggests that alantolactone and isoalantolactone are potential promising anticancer candidates, but additional studies and clinical trials are required to determine their specific intracellular sites of actions and derivative targets in order to fully understand the mechanisms of therapeutic effects to further validate in cancer chemotherapy.

New eudesmenoic acid methyl esters from the seed oil of Jatropha curcas.

Three new eudesmenoic acid methyl esters (1-3), as well as five known compounds, including three germacranolides (4-6) and two eudesmanolides (7 and 8), were isolated from the seed oil of Jatropha curcas. The new compounds were elucidated by means of spectroscopic methods, including extensive NMR spectra. In addition, the structure of 8 was confirmed by a single-crystal X-ray diffraction analysis. Among the isolates, compounds 4-6 were the first reported from the genus Jatropha. Using MTS viability assay, the cytotoxicity of compounds 2-8 were evaluated against HL-60, SMMC-7721, A-549, MCF-7, and SW480 human tumor cell lines. Compounds 4 and 5 showed remarkable cytotoxicity against all the tested cell lines with IC50 values from 0.5 to 3.5 µM, and the new compound 3 displayed selective cytotoxic activity against A-549 cell with an IC50 value of 7.24 µM, but slight cytotoxicity against HL-60 and MCF-7 with IC50 values of 23.77 and 22.37 µM, respectively.

Molecular docking and ADME studies of natural compounds of Agarwood oil for topical anti-inflammatory activity.

Aquilaria agallocha Roxb. family, Thymelaeaceae, is an evergreen plant of South-East Asia, commonly described as aloe wood or agarwood. Traditionally, the bark, root and heartwood are used for their medicinal properties as a folk medicine for hundreds of years. Chemical analyses revealed that the bulk of the oil is constituted by agarospirol (12.5%), jinkoh-eremol (11.8%) and hinesol (8.9%) as major contributor. In the present work, a QSAR model for antiinflammatory activity of 10-epi-γ-Eudesmol, jinkoh-eremol, agarospirol and other compounds has been developed by multiple linear regression method. The r(2) and rCV(2) of a model were 0.89 and 0.81 respectively. In silico molecular docking study suggests that compound 10-epi-γ-Eudesmol, jinkoh-eremol and agarospirol are preferentially more active than other identified compounds with strong binding affinity to major anti-inflammatory and immunomodulatory receptors. The oil displayed a significant and dose dependent reduction of 12-O-tetradecanoylphorobol-13 acetate (TPA)- induced ear edema and MDA activity when compared with vehicle treated mice. Pro-inflammatory cytokines (IL-1ß, IL-6 and TNF-α) were also reduced significantly in a dose dependent manner in all the TPA treated groups as compared to control. The present study indicates that agarwood oil significantly reduced the skin thickness, ear weight, oxidative stress and pro-inflammatory cytokines production in TPA-induced mouse ear inflammation model and contributed towards validation of its traditional use to treat inflammation related ailments.

In vitro and in vivo antitumor effects of the essential oil from the leaves of Guatteria friesiana.

Guatteria friesiana (W. A. Rodrigues) Erkens & Maas (synonym Guatteriopsis friesiana W. A. Rodrigues), popularly known as "envireira", is a medicinal plant found in the Brazilian and Colombian Amazon basin that is used in traditional medicine for various purposes. Recent studies on this species have demonstrated antimicrobial activity. In this study, the antitumor activity of the essential oil from the leaves of G. friesiana (EOGF) and its main components ( α-, ß-, and γ-eudesmol) were determined using experimental models. In the in vitro study, EOGF and its components α-, ß-, and γ-eudesmol displayed cytotoxicity against tumor cell lines, showing IC50 values in the range of 1.7 to 9.4 µg/mL in the HCT-8 and HL-60 cell lines for EOGF, 5.7 to 19.4 µg/mL in the HL-60 and MDA-MB-435 cell lines for α-eudesmol, 24.1 to > 25 µg/mL in the SF-295 and MDA-MB-435 cell lines for ß-eudesmol, and 7.1 to 20.6 µg/mL in the SF-295 and MDA-MB-435 cell lines for γ-eudesmol, respectively. In the in vivo study, the antitumor effect of EOGF was evaluated in mice inoculated with sarcoma 180 tumor cells. Tumor growth inhibition rates were 43.4-54.2 % and 6.6-42.8 % for the EOGF treatment by intraperitoneal (50 and 100 mg/kg/day) and oral (100 and 200 mg/kg/day) administration, respectively. The treatment with EOGF did not significantly affect body mass, macroscopy of the organs, or blood leukocyte counts. Based on these results, we can conclude that EOGF possesses significant antitumor activity and has only low systemic toxicity. These effects could be assigned to its components α-, ß-, and γ-eudesmol.

Neuroprotective effects of 3α-acetoxyeudesma-1,4(15),11(13)-trien-12,6α-olide against dopamine-induced apoptosis in the human neuroblastoma SH-SY5Y cell line.

Dopamine (DA), as a neurotoxin, can elicit severe Parkinson's disease-like syndrome by elevating intracellular reactive oxygen species (ROS) levels and apoptotic activity. We examined the inhibitory effects of 3α-acetoxyeudesma-1,4(15),11(13)-trien-12,6α-olide (AETO), purified from the leaves of Laurus nobilis L., on DA-induced apoptosis and α-synuclein (α-syn) formation in dopaminergic SH-SY5Y cells. AETO decreased the active form of caspase-3 and the levels of p53, which were accompanied by increased levels of Bcl-2 in a dose-dependent manner. Flow cytometric and Western blot analysis showed that AETO significantly inhibited DA-induced apoptosis along with suppression of intracellular tyrosinase activity, ROS generation, quinoprotein, and α-syn formation (P < 0.01). These results indicate that AETO inhibited DA-induced apoptosis, which is closely related to the suppression of intracellular tyrosinase activity and the formation of α-syn, ROS, and quinoprotein in SH-SY5Y cells.

Efficacy of volatile oils (curzerene, furanoeudesma-1, 3-diene and lindestrene) on avian coccidiosis under laboratory conditions.

The coccidicidal efficacy of volatile oils (curzerene, furanoeudesma-1, 3-diene and lindestrene) against unsporulated and sporulated chicken Eimeria species oocysts was tested in three concentrations: 1, 2 & 3 microg/ml. Marked reduction in the number of living oocysts was recorded in exposed groups. The concentration of 3 microg/ml volatile oils induced the highest destructive effect. 58.1% of viable unsporulated oocysts were destroyed. A mean number of 153,800 oocysts was the difference between the total number of the produced oocysts per gram faeces in the group infected with exposed oocysts and that of the group infected with non exposed oocysts being less in the exposed group with more reduction in the vitality of shedding oocysts in the former group. At the meantime, the postmortem and histopathological microscopical examination of the intestine and caecum of the tested group revealed a reduction in the intestinal lesions in the group infected with the exposed oocysts.

Beta-eudesmol suppresses tumour growth through inhibition of tumour neovascularisation and tumour cell proliferation.

In the present study, we investigated the potential anti-angiogenic mechanism and anti-tumour activity of beta-eudesmol using in vitro and in vivo experimental models. Proliferation of human umbilical vein endothelial cells (HUVEC) stimulated with vascular endothelial growth factor (VEGF, 30 ng/ml) and basic fibroblast growth factor (bFGF, 30 ng/ml) was significantly inhibited by beta-eudesmol (50-100 microM). Beta-eudesmol (100 microM) also blocked the phosphorylation of cAMP response element binding protein (CREB) induced by VEGF (30 ng/ml) in HUVEC. Beta-eudesmol (10-100 microM) inhibited proliferation of HeLa, SGC-7901, and BEL-7402 tumour cells in a time- and dose-dependent manner. Moreover, beta-eudesmol treatment (2.5-5 mg/kg) significantly inhibited growth of H(22) and S(180) mouse tumour in vivo. These results indicated that beta-eudesmol inhibited angiogenesis by suppressing CREB activation in growth factor signalling pathway. This is the first study to demonstrate that beta-eudesmol is an inhibitor of tumour growth.