Asiatic acid inhibits lung cancer cell growth in vitro and in vivo by destroying mitochondria

Asiatic acid induces lung cancer toxicity by triggering SRC-mediated ferroptosis

Ferroptosis is a recently discovered form of regulated cell death that shows promise as a novel approach for inducing tumor cell death in cancer treatment, with significant research potential. Asiatic acid (AA), a key component of the traditional Chinese medicine Centella asiatica, has been identified as having potential therapeutic benefits for various diseases, particularly cancer. Non-small cell lung cancer (NSCLC) is a challenging and prevalent form of cancer to treat. In our study, we utilized network pharmacology, molecular docking, and experimental methods to investigate the potential of AA in treating NSCLC and to elucidate its role in inhibiting cancer through the ferroptosis pathway. Through network pharmacology analysis, we identified that AA targets the core NSCLC protein SRC through the ferroptosis pathway. Our experiments demonstrated that treatment with AA led to increased iron accumulation, mitochondrial membrane potential, and expression of ferroptosis markers glutathione peroxidase 4 (GPX4), ferritin heavy chain 1 (FTH1), and acyl-CoA synthetase long chain family member 4 (ACSL4) in NSCLC cells, confirming the induction of ferroptosis. In conclusion, AA has the potential to target SRC and induce NSCLC cell death through the ferroptosis pathway, offering a promising approach for cancer treatment.

Persianolide-A, an eudesmanolide-type sesquiterpene lactone from Artemisia kopetdaghensis, induces apoptosis by regulating ERK signaling pathways

Background and purpose

Herbal components, particularly sesquiterpenes, are progressively recognized as a crucial resource for developing effective therapeutic agents for breast cancer. In this study, the effect of a sesquiterpene lactone known as 8-O-dihydroxy-11a,13-dihydroeudesma-4(15)-en-12,6a-olide (persianolide- A) was examined in breast cancer cell lines.

Experimental approach

MDA-MB-231 and MCF-7 cancer cells were grown in DMEM solution with 10% FBS. Then, an MTT assay was performed to evaluate cell viability. Apoptosis was detected by annexin-PI staining. A caspase 3/7 activity assay kit was used to assess the activity of caspase-3 and caspase-7. Protein expression of Bcl-2, Bax, and p-ERK1/2 was determined by western blotting.

Findings/Results

This study showed that the IC50 values of the persianolide-A for MCF-7 and MDA-MB- 468 cells are 34.76 and 54.48 μM, respectively. In addition, persianolide-A showed a significant increase in apoptosis in both MDAMB-231 and MCF-7 breast cancer cell lines. Persianolide-A significantly increased the expression of the pro-apoptotic protein Bax and decreased the expression of the anti-apoptotic protein Bcl-2. Also, presinolide-A treatment led to a substantial increase in caspase activity with a ratio of 3/7 in both MCF- 7 and MDA-MB-231 cancer cells. In addition, the study showed that persianolide-A decreased the expression of p-ERK1/2 protein.

Conclusion and implications

The results of this study suggest that persianolide-A, sourced from Artemisia kopetdaghensis, induces cell apoptosis in breast cancer cell types. The molecular mechanisms could be implicated in the modulation of the ERK1/2 signaling pathway.

Asiatic acid rescues intestinal tissue by suppressing molecular, biochemical, and histopathological changes associated with the development of ulcerative colitis

Asiatic acid (AA) is a polyphenolic compound with potent antioxidative and anti-inflammatory activities that make it a potential choice to attenuate inflammation and oxidative insults associated with ulcerative colitis (UC). Hence, the present study aimed to evaluate if AA can attenuate molecular, biochemical, and histological alterations in the acetic acid-induced UC model in rats. To perform the study, five groups were applied, including the control, acetic acid-induced UC, UC-treated with 40 mg/kg aminosalicylate (5-ASA), UC-treated with 20 mg/kg AA, and UC-treated with 40 mg/kg AA. Levels of different markers of inflammation, oxidative stress, and apoptosis were studied along with histological approaches. The induction of UC increased the levels of lipid peroxidation (LPO) and nitric oxide (NO). Additionally, the nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream antioxidant proteins [catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GPx), and glutathione reductase (GR)] were down-regulated in the colon tissue. Moreover, the inflammatory mediators [myeloperoxidase (MPO), monocyte chemotactic protein 1 (MCP1), prostaglandin E2 (PGE2), nuclear factor-kappa B (NF-κB), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β)] were increased in the colon tissue after the induction of UC. Notably, an apoptotic response was developed, as demonstrated by the increased caspase-3 and Bax and decreased Bcl2. Interestingly, AA administration at both doses lessened the molecular, biochemical, and histopathological changes following the induction in the colon tissue of UC. In conclusion, AA could improve the antioxidative status and attenuate the inflammatory and apoptotic challenges associated with UC.

Can Asiatic Acid from Centella asiatica Be a Potential Remedy in Cancer Therapy?-A Review

Centella asiatica has been recognized for centuries in Eastern medicine for its pharmacological properties. Due to the increasing prevalence of oncological diseases worldwide, natural substances that could qualify as anticancer therapeutics are becoming increasingly important subjects of research. This review aims to find an innovative use for asiatic acid (AA) in the treatment or support of cancer therapy. It has been demonstrated that AA takes part in inhibiting phosphorylation, inducing cell death, and reducing tumor growth and metastasis by influencing important signaling pathways, such as PI3K, Akt, mTOR, p70S6K, and STAT3, in cancer cells. It is also worth mentioning the high importance of asiatic acid in reducing the expression of markers such as N-cadherin, β-catenin, claudin-1, and vimentin. Some studies have indicated the potential of asiatic acid to induce autophagy in cancer cells through changes in the levels of specific proteins such as LC3 and p62. It can also act as an anti-tumor immunotherapeutic agent, thanks to its inductive effect on Smad7 in combination with naringenin (an Smad3 inhibitor). It seems that asiatic acid may be a potential anticancer drug or form of adjunctive therapy. Further studies should take into account safety and toxicity issues, as well as limitations related to the pharmacokinetics of AA and its low oral bioavailability.

Exploration of anti‑osteosarcoma activity of asiatic acid based on network pharmacology and in vitro experiments

Osteosarcomas are malignant bone tumors that typically originate in the epiphyses of the long bones of the extremities in adolescents. Asiatic acid has been reported to possess anti‑inflammatory, neuroprotective, antidiabetic, antitumor and antimicrobial activities. The present study used a combination of network pharmacological prediction and in vitro experimental validation to explore the potential pharmacological mechanism of asiatic acid against osteosarcoma. A total of 78 potential asiatic acid targets in osteosarcoma were identified using databases. Kyoto Encyclopedia of Genes and Genomes analysis indicated that the PI3K/AKT and MAPK signaling pathways are essential in the treatment of osteosarcoma with asiatic acid. Molecular docking revealed binding of asiatic acid to EGFR, Caspase‑3, ESR1, HSP90AA1, IL‑6 and SRC proteins. asiatic acid inhibited proliferation through G2/M cell cycle arrest in osteosarcoma cells. In addition, asiatic acid induced mitochondria‑dependent apoptosis as demonstrated by increases in Bax and VDAC1 expression, and a decrease in Bcl‑2 protein expression. The increased autophagosomes, increased LC3‑II/I ratios and decreased p62 expression in the treatment group indicated that asiatic acid triggered autophagy. In addition, asiatic acid decreased the levels of phosphorylated (p‑)PI3K/PI3K and p‑AKT/AKT, increased reactive oxygen species (ROS) and upregulated the levels of p‑ERK1/2/ERK1/2, p‑p38/p38 and p‑JNK/JNK in osteosarcoma cells. These results demonstrated that asiatic acid inhibited osteosarcoma cells proliferation by inhibiting PI3K/AKT and activating ROS/MAPK signaling pathways, suggesting asiatic acid is a potential agent against osteosarcoma.

Bioactive compounds from Actinidia arguta fruit as a new strategy to fight glioblastoma

In recent years, there has been a significant demand for natural products as a mean of disease prevention or as an alternative to conventional medications. The driving force for this change is the growing recognition of the abundant presence of valuable bioactive compounds in natural products. On recent years Actinia arguta fruit, also known as kiwiberry, has attracted a lot of attention from scientific community due to its richness in bioactive compounds, including phenolic compounds, organic acids, vitamins, carotenoids and fiber. These bioactive compounds contribute to the fruit's diverse outstanding biological activities such as antioxidant, anti-inflammatory, neuroprotective, immunomodulatory, and anti-cancer properties. Due to these properties, the fruit may have the potential to be used in the treatment/prevention of various types of cancer, including glioblastoma. Glioblastoma is the most aggressive form of brain cancer, displaying 90 % of recurrence rate within a span of 2 years. Despite the employment of an aggressive approach, the prognosis remains unfavorable, emphasizing the urgent requirement for the development of new effective treatments. The preclinical evidence suggests that kiwiberry has potential impact on glioblastoma by reducing the cancer self-renewal, modulating the signaling pathways involved in the regulation of the cell phenotype and metabolism, and influencing the consolidation of the tumor microenvironment. Even though, challenges such as the imprecise composition and concentration of bioactive compounds, and its low bioavailability after oral administration may be drawbacks to the development of kiwiberry-based treatments, being urgent to ensure the safety and efficacy of kiwiberry for the prevention and treatment of glioblastoma. This review aims to highlight the potential impact of A. arguta bioactive compounds on glioblastoma, providing novel insights into their applicability as complementary or alternative therapies.

An environmentally insensitive fluorescent probe for G4 DNA detection: Design, synthesis, and mechanism studies

G4 DNA structure highly localized to functionally important sites within the human genome, has been identified as a biomarker for regulation of multiple biological processes. Identification G4-responsive fluorescence probes has broad application prospects for addressing G4 biological functions, as well as developing of new families of anticancer drugs. However, some currently designed G4 DNA probes may suffer from serious solvent-dependent effect, and cause unspecific fluorescence that masks the specific signal from G4 DNA. Herein, with a bulky imidazole-cored molecular rotor fusing in D-A building block of carbazole-pyridinium, we constructed a new probe ACPS. This new probe with desirable environmentally insensitive property exhibited a "fluorescence-off" state in various polarity solvents. In the presence of G4 DNA, the intra-molecular rotations would be restricted, triggering intense fluorescence enhancement. Especially, probe ACPS bound to G4 DNA structures with superior selectivity, exhibiting much weaker fluorescence response in the presence of non-G4 DNA structures. This probe was also able to realize fluorescence visualization in cell imaging. Collectively, the probe design strategy eliminates the background fluorescence caused by uncontrollable environmental polarity change, thereby achieving high-fidelity sensing G4 DNA structures in complicated systems.

Design, synthesis and anti-tumor activity of asiatic acid derivatives as VEGF inhibitors

The VEGF receptor is mock-coupled with a known active compound and the active groups of the inhibitor which can bind to VEGF were analyzed. Using asiatic acid as a lead compound, 10 novel skeleton candidate compounds were designed through introduction of the active groups onto the special location and synthesized simultaneously. Furthermore, the structure of these compounds was determined by ¹H NMR, ¹³C NMR and MS and 9 compounds were identified as the new compounds. Moreover, the in vitro anti-tumor activities of these new compounds were determined by MTT assay on two cancer cell lines (HepG2 and SGC-7901). The results showed that compounds I₁ and II₂ have more potent anticancer activity than positive control drugs such as gefitinib and paclitaxel.

Quaternary Ammonium Salt Strategy and Molecular Docking Studies of Novel 5-Acyl-8-(Arylamino)-Quinolines by Acetyl and Methanesulfonyl Chloride for Dual Evaluation Bioactivity

Six quinoline derivatives containing quaternary ammonium salts and acyl chloride groups were synthesized from ethyl 8-chloro-[1,3]dioxolo[4,5-g]quinoline-7-carboxylate in several step. With berberine as the positive control, three human cancer cell lines (HCT-116, Hela and A549) and human normal liver L-02 cell lines were used to evaluate the cytotoxicity of the newly synthesized compounds in vitro. Compound (V-X) showed good antitumor activity, and the test result of compound (VII) was better than that of positive control group. In terms of antibacterial activity, compound (V-X) has obvious inhibitory effect on Staphylococcus aureus (ATCC 29213) and Escherichia coli (ATCC 8739), and its antibacterial activity is about 1-4 times that of positive control amoxicillin and 1-2 times that of ciprofloxacin. Among them, the most effective compounds (VII) and (X) have 4-fold the antibacterial activity of amoxicillin and 2-fold the antibacterial activity of ciprofloxacin.

Supplementary Information

The online version contains supplementary material available at 10.1134/S1068162023020097.

Synergistic Combination of Luteolin and Asiatic Acid on Cervical Cancer In Vitro and In Vivo

Cervical cancer is an important issue globally because it is the second most common gynecological malignant tumor and conventional treatment effects have been shown to be limited. Lut and AsA are plant-derived natural flavonoid and triterpenoid products that have exhibited anticancer activities and can modulate various signaling pathways. Thus, the aim of the present study was to evaluate whether Lut combined with AsA could enhance the anticancer effect to inhibit cervical cancer cell proliferation and examine the underlying molecular mechanisms in vitro and in vivo. The results of a CCK-8 assay showed that Lut combined with AsA more effectively inhibited the proliferation of CaSki and HeLa cells than Lut or AsA treatment alone. Lut combined with AsA caused apoptosis induction and sub-G1-phase arrest in CaSki and HeLa cells, as confirmed by flow cytometry, mitoROS analysis, antioxidant activity measurement and western blot assay. In addition, Lut combined with AsA significantly inhibited the cell migration ability of CaSki and HeLa cells in a wound-healing assay. Furthermore, Lut combined with AsA induced apoptosis and inhibited migration through downregulated PI3K/AKT (PI3K, AKT and p70S6K), JNK/p38 MAPK and FAK (integrin β1, paxillin and FAK) signaling and upregulated ERK signaling. In an in vivo study, Lut combined with AsA markedly inhibited cervical cancer cell-derived xenograft tumor growth. Collectively, the present study showed that Lut combined with AsA may be used as an anticancer agent to improve the prognosis of cervical cancer. Indeed, with additional research to develop standardized dosages, Lut and AsA combination therapy could also be applied in clinical medicine.

Mitochondrion-Targeted NIR Therapeutic Agent Suppresses Melanoma by Inducing Apoptosis and Cell Cycle Arrest via E2F/Cyclin/CDK Pathway

Malignant melanoma is the most fatal form of skin cancer worldwide, and earlier diagnosis and more effective therapies are required to improve prognosis. As a possible solution, near-infrared fluorescent heptamethine cyanine dyes have been shown to be useful for tumor diagnosis and treatment. Here, we synthesized a novel theranostic agent, IR-817, a multifunctional bioactive small-molecule that has near-infrared emission, targets mitochondria in cancer cells, and has selective anti-cancer effects. In in vitro experiments, IR-817 preferentially accumulated in melanoma cells through organic anion transporting polypeptide transporters but also selectively inhibited the growth of tumor cells by inducing mitochondrial-dependent intrinsic apoptosis. Mechanistically, IR-817 caused G0/G1 cell cycle arrest by targeting the E2F/Cyclin/CDK pathway. Finally, IR-817 significantly suppressed the growth of xenograft tumors in zebrafish and mice. Immunohistochemical staining and hematoxylin and eosin staining revealed that IR-817 induced apoptosis and inhibited tumor cell proliferation without notable side effects. Therefore, mitochondrial-targeting theranostic agent IR-817 may be promising for accurate tumor diagnosis, real-time monitoring, and safe anti-cancer treatments.

Biotechnological Intervention and Secondary Metabolite Production in Centella asiatica L

Centella asiatica L., commonly known as Gotu kola, Indian pennywort, and Asiatic pennyworts, is an herbaceous perennial plant that belongs to the family Apiaceae and has long been used in the traditional medicine system. The plant is known to produce a wide range of active metabolites such as triterpenoids including asiatic acid, asiaticoside, brahmoside, and madecassic acid along with other constituents including centellose, centelloside, and madecassoside, etc., which show immense pharmacological activity. Due to its beneficial role in neuroprotection activity, the plant has been considered as a brain tonic. However, limited cultivation, poor seed viability with low germination rate, and overexploitation for decades have led to severe depletion and threatened its wild stocks. The present review aimed to provide up-to-date information on biotechnological tools applied to this endangered medicinal plant for its in vitro propagation, direct or indirect regeneration, synthetic seed production, strategies for secondary metabolite productions including different elicitors. In addition, a proposed mechanism for the biosynthesis of triterpenoids is also discussed.

Identification of potential inhibitory analogs of metastasis tumor antigens (MTAs) using bioactive compounds: revealing therapeutic option to prevent malignancy

The deeper understanding of metastasis phenomenon and detection of drug targets could be a potential approach to minimize cancer mortality. In this study, attempts were taken to unmask novel therapeutics to prevent metastasis and cancer progression. Initially, we explored the physiochemical, structural and functional insights of three metastasis tumor antigens (MTAs) and evaluated some plant-based bioactive compounds as potent MTA inhibitors. From 50 plant metabolites screened, isoflavone, gingerol, citronellal and asiatic acid showed maximum binding affinity with all three MTA proteins. The ADME analysis detected no undesirable toxicity that could reduce the drug likeness properties of top plant metabolites. Moreover, molecular dynamics studies revealed that the complexes were stable and showed minimum fluctuation at molecular level. We further performed ligand-based virtual screening to identify similar drug molecules using a large collection of 376,342 compounds from DrugBank. The results suggested that several structural analogs (e.g., tramadol, nabumetone, DGLA and hydrocortisone) may act as agonist to block the MTA proteins and inhibit cancer progression at early stage. The study could be useful to develop effective medications against cancer metastasis in future. Due to encouraging results, we highly recommend further in vitro and in vivo trials for the experimental validation of the findings.

Centella asiatica-Derived Endothelial Paracrine Restores Epithelial Barrier Dysfunction in Radiation-Induced Enteritis

Radiation-induced enteritis is frequently observed following radiotherapy for cancer or occurs due to radiation exposure in a nuclear accident. The loss of the epithelial integrity leads to ‘leaky gut’, so recovery of damaged epithelium is an important strategy in therapeutic trials. Centella asiatica (CA), a traditional herbal medicine, is widely used for wound healing by protecting against endothelial damage. In this study, we investigated the radio-mitigating effect of CA, focusing on the crosstalk between endothelial and epithelial cells. CA treatment relieved radiation-induced endothelial dysfunction and mitigated radiation-induced enteritis. In particular, treatment of the conditioned media from CA-treated irradiated endothelial cells recovered radiation-induced epithelial barrier damage. We also determined that epidermal growth factor (EGF) is a critical factor secreted by CA-treated irradiated endothelial cells. Treatment with EGF effectively improved the radiation-induced epithelial barrier dysfunction. We also identified the therapeutic effects of CA-induced endothelial paracrine in a radiation-induced enteritis mouse model with epithelial barrier restoration. Otherwise, CA treatment did not show radioprotective effects on colorectal tumors in vivo. We showed therapeutic effects of CA on radiation-induced enteritis, with the recovery of endothelial and epithelial dysfunction. Thus, our findings suggest that CA is an effective radio-mitigator against radiation-induced enteritis.

Recent Advances Regarding the Molecular Mechanisms of Triterpenic Acids: A Review (Part I)

Triterpenic acids are phytocompounds with a widespread range of biological activities that have been the subject of numerous in vitro and in vivo studies. However, their underlying mechanisms of action in various pathologies are not completely elucidated. The current review aims to summarize the most recent literature, published in the last five years, regarding the mechanism of action of three triterpenic acids (asiatic acid, oleanolic acid, and ursolic acid), corelated with different biological activities such as anticancer, anti-inflammatory, antidiabetic, cardioprotective, neuroprotective, hepatoprotective, and antimicrobial. All three discussed compounds share several mechanisms of action, such as the targeted modulation of the PI3K/AKT, Nrf2, NF-kB, EMT, and JAK/STAT3 signaling pathways, while other mechanisms that proved to only be specific for a part of the triterpenic acids discussed, such as the modulation of Notch, Hippo, and MALAT1/miR-206/PTGS1 signaling pathway, were highlighted as well. This paper stands as the first part in our literature study on the topic, which will be followed by a second part focusing on other triterpenic acids of therapeutic value.

The Potential of Centella asiatica Herb and Cyperus rotundus L. Rhizomes Extract as a Chemoprevention Agent for Lung Cancer

BACKGROUND: The number of smokers is increasing in Indonesia. Cigarette smoke can cause many diseases, such as lung cancer. Centella asiatica (CAS) and Cyperus rotundus L. rhizomes (CRR) exhibit anti-cancer effects. AIM: The study examined the cytotoxic effects of CRR and CAS extracts in lung cancer cells. METHODOLOGY: This research used the maceration method to extract the CAS and CRR powder and methanol solvent. Extraction was tested at 600μl, 400μl, 200 μl, 100 μl, and 50 μl to determine the effect of compound cytotoxicity causing 50% cell death or IC50. Cytotoxicity tests used the MTT method to obtain purple formation crystals and used an ELISA reader to obtain absorbance values. RESULTS: CRR and CAS extract shows a low cytotoxicity effect. IC50 of CRR and CAS methanol extracts was 235 μg/ml and 279 μg/ml, respectively. CONCLUSION: CRR and CAS extracts were proven to show chemopreventive activities against lung cancer cells.

Asiatic Acid Attenuates Osteoporotic Bone Loss in Ovariectomized Mice Through Inhibiting NF-kappaB/MAPK/ Protein Kinase B Signaling Pathway

Osteoporosis is a condition associated with osteolytic bone disease that is primarily characterized by inordinate osteoclast activation. Protein kinase B (Akt) pathways activated by receptor activator of nuclear factor kappa-B ligand (RANKL) are essential for osteoclastogenesis. Asiatic acid (AA) is a natural pentacyclic triterpenoid compound extracted from a traditional Chinese herb that exhibits a wide range of biological activities. AA has been found to alleviate the hypertrophic and fibrotic phenotype of chondrocytes via the Akt signaling pathway. In this study, we investigated whether AA alleviated bone loss by inhibiting the Akt signaling pathway during osteoclastogenesis and its effect on osteoblasts. The effect of AA cytotoxicity on mouse bone marrow-derived macrophages/monocytes (BMMs) was evaluated in vitro using a Cell Counting Kit-8 assay. The effects of AA on osteoclast differentiation and function were detected using tartrate-resistant acid phosphatase (TRAP) staining and a pit formation assay. A Western blot and qRT-PCR were conducted to evaluate the expression of osteoclast-specific genes and protein signaling molecules. In addition, alkaline phosphatase and alizarin red staining were performed to assess osteoblast differentiation and mineralization. The bone protective effect of AA was investigated in vivo using ovariectomized mice. we found that AA could dose-dependently inhibit RANKL-induced osteoclastogenesis. Moreover, the pit formation assay revealed that osteoclast function was suppressed by treatment with AA. Moreover, the expression of osteoclast-specific genes was found to be substantially decreased during osteoclastogenesis. Analysis of the molecular mechanisms showed that AA could inhibit NF-kappaB/MAPK/Akt signaling pathway, as well as the downstream factors of NFATc1 in the osteoclast signaling pathway activated by RANKL. However, AA did not significantly promote osteoblast differentiation and mineralization. The in vivo experiments suggested that AA could alleviate ovariectomy-induced bone loss in ovariectomized mice. Our results demonstrate that AA can inhibit osteoclastogenesis and prevent ovariectomy-induced bone loss by inhibiting the NF-kappaB/MAPK/Akt signaling pathway. The discovery of the new molecular mechanism that AA inhibits osteoclastogenesis provides essential evidence to support the use of AA as a potential drug for the treatment of osteoclast-related diseases.

Asiatic Acid Encapsulated Exosomes of Hepatocellular Carcinoma Inhibit Epithelial-Mesenchymal Transition Through Transforming Growth Factor Beta/Smad Signaling Pathway

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death in many countries, which accounts for more than 80% of primary liver cancers. Better understanding of the biology of HCC and more therapeutic strategies are urgently needed to improve the current situation. Exosomes, lipid-bound particles derived from cells, have been revealed to play versatile roles in mediating communication between tumor and its microenvironment. Thus, exosomes could act as potential drug delivery systems in cancer treatment. This study aimed to investigate the effect of asiatic acid (AA)-loaded exosomes on the proliferation and migration of HCC cells and clarify the underlying mechanisms. HCC cells were treated with AA-loaded exosomes and cell vitality, migration and invasion were examined. Compared with free AA, AA-loaded exosomes significantly reduced cell vitality, migration, invasion and epithelial mesenchymal transition (EMT). And the inhibition was enhanced as AA concentration went up. Moreover, the expression of proteins involved in EMT and TGF-β/Smad pathway such as TGF-β1, Smad4 and Vimentin were decreased while E-cadherin was up-regulated. Collectively, these findings demonstrate that HCC derived exosomes display as potential drug delivery vehicles in HCC treatment. And AA-loaded exosomes might work by inhibiting EMT through inactivating TGF-β/Smad pathway.

In vitro anticancer activity of a pentacyclic triterpenoid via the mitochondrial pathway in bone-invasive oral squamous cell carcinoma

Context:

Oral cancer is the most dreadful cancer worldwide with a 5-year survival rate of approximately 50%. Anticancer therapies such as chemotherapy and radiotherapy result in severe side effects.

Aim:

We aimed to evaluate the in vitro anticancer activity of Asiatic acid (AA) on bone-invasive oral squamous cell carcinoma (BHY) cell line.

Settings and Design:

This was an in vitro laboratory setting.

Materials and Methods:

BHY cell lines were used for the experiment. Confocal microscopy was used to observe cellular alterations. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to determine the IC50 concentration of AA and flow cytometry to analyze the percentage of cells in each phase of the cell cycle post treatment. Immunoblot assays and semiquantitative reverse transcriptase-polymerase chain reaction (rt-PCR) were used to study the expression level of genes involved.

Statistical Analysis Used:

Student's t-test and one-way analysis of variance were used for statistical analysis.

Results:

IC50 concentration of AA was 15.6 μM. On flow cytometry analysis, treatment with 15.6 μM and 31.25 μM of AA for 24 h increased the percentage of cells in the G2/M phase to 45.63% and 53.12%, respectively, compared to 9.62% in control group. Immunoblot analysis and semiquantitative rt-PCR demonstrated an upregulation of p53, cyclin-dependent kinase inhibitors (p21 and p27), caspase-3, caspase-9, cytochrome c and Bax in a time-dependent manner and downregulation of cyclins and anti-apoptotic protein Bcl-2 (**P < 0.05, ***P < 0.001 versus control) post AA treatment.

Conclusion:

AA induces apoptosis via the mitochondrial-dependent pathway and causes cell cycle arrest at the G2/M phase in BHY cell line.

Molecular docking and simulation studies of phytocompounds derived from Centella asiatica and Andrographis paniculata against hexokinase II as mitocan agents

Hexokinase II (HK2), a glycolytic enzyme is commonly overexpressed in most cancer types. The overexpression of HK2 is reported to promote the survival of cancer cells by facilitating the constant ATP generation and protecting the cancer cell against apoptotic cell death. Hence, HK2 is considered as potential target of many mitochondria targeting anticancerous agents (referred to as mitocans). Most of the existing mitocans are synthetic and hence such compounds are observed to exhibit adverse effects, witnessed through many experimental outcomes. These limitations necessitates hunting for an alternative source of mitocans with minimum/no side effects. The need for an alternative therapy points towards the ethnomedicinal herbs, known for their minimal side effects and effectiveness. Henceforth recent studies have put forth the effort to utilize anticancer herbs in formulating naturally derived mitocans as an add-on to improve cancer therapeutics. So, our study aims to explore the HK2 targeting potential of phytocompounds from the selected anticancerous herbs Andrographis paniculata (AP) and Centella asiatica (CA). 60 phytocompounds collectively from CA and AP were docked against HK2 and drug-likeness prediction of the selected phytocompounds was performed to screen the best possible ligand for HK2. Furthermore, the docked complexes were subjected to molecular dynamics simulations (MDS) to analyse the molecular mechanism of protein-ligand interactions. The results of the study suggest that the natural compounds asiatic acid and bayogenin (from CA) and andrographolide (from AP) can bepotential natural mitocans by targeting HK2. Further experimental studies (in-vitro and in-vivo) are required to validate the results.

Corosolic acid and its structural analogs: A systematic review of their biological activities and underlying mechanism of action

BACKGROUND

The corosolic acid (CA), also known as plant insulin, is a pentacyclic triterpenoid extracted from plants such as Lagerstroemia speciosa. It has been shown to have anti-diabetic, anti-inflammatory and anti-tumor effects. Its structural analogs ursolic acid (UA), oleanolic acid (OA), maslinic acid (MA), asiatic acid (AA) and betulinic acid (BA) display similar individual pharmacological activities to those of CA. However, there is no systematic review documenting pharmacological activities of CA and its structural analogues. This study aims to fill this gap in literature.

PURPOSE

This systematic review aims to summarize the medical applications of CA and its analogues.

METHODS

A systematic review summarizes and compares the extraction techniques, pharmacokinetic parameters, and pharmacological effects of CA and its structural analogs. Hypoglycemic effect is one of the key inclusion criteria for searching Web of Science, PubMed, Embase and Cochrane databases up to October 2020 without language restrictions. 'corosolic acid', 'ursolic acid', 'oleanolic acid', 'maslinic acid', 'asiatic acid', 'betulinic acid', 'extraction', 'pharmacokinetic', 'pharmacological' were used to extract relevant literature. The PRISMA guidelines were followed.

RESULTS

At the end of the searching process, 140 articles were selected for the systematic review. Information of CA and five of its structural analogs including UA, OA, MA, AA and BA were included in this review. CA and its structural analogs are pentacyclic triterpenes extracted from plants and they have low solubilities in water due to their rigid scaffold and hydrophobic properties. The introduction of water-soluble groups such as sugar or amino groups could increase the solubility of CA and its structural analogs. Their biological activities and underlying mechanism of action are reviewed and compared.

CONCLUSION

CA and its structural analogs UA, OA, MA, AA and BA are demonstrated to show activities in lowering blood sugar, anti-inflammation and anti-tumor. Their oral absorption and bioavailability can be improved through structural modification and formulation design. CA and its structural analogs are promising natural product-based lead compounds for further development and mechanistic studies.

Cancer stem cells and strategies for targeted drug delivery

Cancer stem cells (CSCs) are a small proportion of cancer cells with high tumorigenic activity, self-renewal ability, and multilineage differentiation potential. Standard anti-tumor therapies including conventional chemotherapy, radiation therapy, and molecularly targeted therapies are not effective against CSCs, and often lead to enrichment of CSCs that can result in tumor relapse. Therefore, it is hypothesized that targeting CSCs is key to increasing the efficacy of cancer therapies. In this review, CSC properties including CSC markers, their role in tumor growth, invasiveness, metastasis, and drug resistance, as well as CSC microenvironment are discussed. Further, CSC-targeted strategies including the use of targeted drug delivery systems are examined.

Anticancer effects of asiatic acid against doxorubicin-resistant breast cancer cells via an AMPK-dependent pathway in vitro

BACKGROUND AND PURPOSE

Asiatic acid is one of the active compounds isolated from Centella asiatica and has been used to treat many diseases, including hypertension, pulmonary fibrosis, and cancer. It exhibits anticancer effects in many cancers, such as ovarian, lung and colon cancer; however, its anticancer effects in breast cancer and the underlying mechanism are not fully understood. Chemoresistance is often induced after the use of chemotherapy, and it is a challenging problem in cancer therapy. The effects of asiatic acid on chemoresistance in breast cancer have never been studied. Therefore, the aim of the present study was to examine the anticancer effects of asiatic acid in doxorubicin-resistant breast cancer MCF-7 cells.

METHODS

The cells were incubated with asiatic acid at 0-160 μM for 2-24 h. Cell viability and cytotoxicity were evaluated by 3-[4, 5-dimethyl-2-thiazolyl]-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. Florescent images were taken using a confocal microscope. P-gp function and apoptosis assays were performed using flow cytometry. Caspase activity was measured with the Caspase-Glo™ Assay System. The phosphorylation and expression of relevant proteins were assessed by western blots. Molecular docking was performed and scored by AutoDock. Cellular thermal shift assay (CETSA) was applied for experimental valuation.

RESULTS

Our data demonstrated that asiatic acid induced cell death in multiple ways, including reactive oxygen species production, adenosine triphosphate (ATP) content reduction, and adaptive immunity balance via intrinsic apoptosis, AMP-activated protein kinase (AMPK), programmed death-ligand 1 (PD-L1), and indirect nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) transcriptional pathways, using experimental validation and in silico analysis. Moreover, asiatic acid also enhanced the sensitivity of doxorubicin-resistant MCF-7 cells to doxorubicin by improving P-glycoprotein (P-gp) function.

CONCLUSIONS

This study provides evidence that asiatic acid has strong anticancer effects to reverse multidrug resistance and could be developed as a promising adjuvant drug for the treatment of chemoresistant cancer.

Asiatic acid inhibits angiogenesis and vascular permeability through the VEGF/VEGFR2 signaling pathway to inhibit the growth and metastasis of breast cancer in mice

Anti-angiogenic medicines have been evaluated as anticancer therapies, however, their use remains limited in clinical practice due to associated adverse effects. Asiatic acid (AA) is known to have broad-spectrum anticancer properties, however, its effects on angiogenesis in breast cancer remain to be fully established. In this study, we analyzed the inhibitory effects of AA on angiogenesis using human umbilical vein endothelial cells (HUVECs) cultured in vitro and on the growth and metastasis of a subcutaneous breast cancer 4T1 tumor model and a lung metastasis model in vivo. AA significantly inhibited HUVECs proliferation, migration, and tube formation in vitro. In vivo, AA significantly reduced the microvascular density and blood vascular permeability in breast cancer tumors and inhibited growth and lung metastasis. AA inhibited the expression of vascular endothelial growth factor (VEGF) in HUVECs and subsequently downregulated the phosphorylation of vascular endothelial growth factor receptor 2 (VEGFR2) and its downstream target proteins including ERK1/2, Src, and FAK. These results indicate that AA significantly inhibits angiogenesis and blood vessel permeability through the VEGF/VEGFR2 signal axis to inhibit the growth and metastasis of breast cancer. Our data strongly demonstrate the potential applications of AA in the treatment of breast cancer.

Actions and Therapeutic Potential of Madecassoside and Other Major Constituents of Centella asiatica: A Review

Centella asiatica is a popular herb well-known for its wide range of therapeutic effects and its use as a folk medicine for many years. Its therapeutic properties have been well correlated with the presence of asiaticoside, madecassoside, asiatic and madecassic acids, the pentacyclic triterpenes. The herb has been extensively known to treat skin conditions; nevertheless, several pre-clinical and clinical studies have scientifically demonstrated its effectiveness in other disorders. Among the active constituents that have been identified in Centella asiatica, madecassoside has been the subject of only a relatively small number of scientific reports. Therefore, this review, while including other major constituents of this plant, focuses on the therapeutic potential, pharmacokinetics and toxicity of madecassoside.

Asiatic Acid Induces Endoplasmic Reticulum Stress and Activates the Grp78/IRE1α/JNK and Calpain Pathways to Inhibit Tongue Cancer Growth

Asiatic acid (AA) has been shown to induce apoptotic death in a range of cancers, but the mechanisms whereby it can inhibit tongue cancer growth have yet to be clarified. Herein, we explored the effects of AA on tongue cancer cells and found that it induced their apoptotic death in vitro and in vivo, while additionally impairing xenograft tumor growth in vivo. From a mechanistic perspective, AA treatment was associated with increases in levels of calcium and the calcium- dependent protease calpain, and it further induced endoplasmic reticulum (ER) stress and consequent Grp78-related IRE1α and JNK phosphorylation, ultimately driving caspase-3 activation and apoptotic death. Together, these results highlight AA as a promising tool for the therapeutic treatment of tongue cancer in clinical practice.

Anti-Cancer Effects of Asiatic Acid, a Triterpene from Centilla asiatica L: A Review

BACKGROUND

Centilla asiatica L is a medicinal herb that has been widely used in folk medicine to treat various diseases. Asiatic Acid (AA), a triterpene and a known component of this herb, has been shown to display important biological activities, including anti-inflammatory, antibacterial, antidiabetic and antihyperlipidemic, neuroprotective, anxiolytic and antidepressant, hepatoprotective, pancreas protective, and cardio- protective.

OBJECTIVE

This review focuses on AA's anti-cancer effects on the basis of published literature found in a number of databases such as PubMed and Science Direct. Emphasis has been given to the mechanisms of action of its anti-cancer effect.

METHODS

A literature survey was conducted using known databases such as PubMed and Science Direct using the keywords 'Asiatic acid', pairing with 'cancer', 'tumor', 'anti-cancer effect', 'cytotoxic effect', 'anti-tumor activity', 'cell line', 'animal cancer', and 'human cancer'.

RESULTS

Findings suggest that AA exerts anti-cancer effects in several test systems through various pathways, including oxidative/antioxidant, anti-inflammatory, cytotoxicity, apoptotic cell death, necrosis, anti-angiogenesis, inhibition of proliferation and cell migration, and chemoprevention.

CONCLUSION

AA may be an effective plant-based cancer chemotherapeutic agent and a promising lead for the development of potent anticancer drugs.

Identification of potential inhibitory analogs of metastasis tumor antigens (MTAs) using bioactive compounds: revealing therapeutic option to prevent malignancy.. [DOI: 10.1101/2020.10.19.345975]

The deeper understanding of metastasis phenomenon and detection of drug targets could be a potential approach to minimize cancer mortality. In this study, attempts were taken to unmask novel therapeutics to prevent metastasis and cancer progression. Initially, we explored the physiochemical, structural and functional insights of three metastasis tumor antigens (MTAs) and evaluated some plant based bioactive compounds as potent MTA inhibitors. From 50 plant metabolites screened, isoflavone, gingerol, citronellal and asiatic acid showed maximum binding affinity with all three MTA proteins. The ADME analysis detected no undesirable toxicity that could reduce the drug likeness properties of top plant metabolites. Moreover, molecular dynamics studies revealed that the complexes were stable and showed minimum fluctuation at molecular level. We further performed ligand based virtual screening to identify similar drug molecules using a large collection of 3,76,342 compounds from DrugBank. The results suggested that several structural analogs (e.g. Tramadol, Nabumetone, DGLA, Hydrocortisone) may act as agonist to block the MTA proteins and inhibit cancer progression at early stage. The study could be useful to develop effective medications against cancer metastasis in future. Due to encouraging results, we highly recommend furtherin vitroandin vivotrials for the experimental validation of the findings.

Natural Agents Targeting Mitochondria in Cancer

Mitochondria are the key energy provider to highly proliferating cancer cells, and are subsequently considered one of the critical targets in cancer therapeutics. Several compounds have been studied for their mitochondria-targeting ability in cancer cells. These studies’ outcomes have led to the invention of “mitocans”, a category of drug known to precisely target the cancer cells’ mitochondria. Based upon their mode of action, mitocans have been divided into eight classes. To date, different synthetic compounds have been suggested to be potential mitocans, but unfortunately, they are observed to exert adverse effects. Many studies have been published justifying the medicinal significance of large numbers of natural agents for their mitochondria-targeting ability and anticancer activities with minimal or no side effects. However, these natural agents have never been critically analyzed for their mitochondria-targeting activity. This review aims to evaluate the various natural agents affecting mitochondria and categorize them in different classes. Henceforth, our study may further support the potential mitocan behavior of various natural agents and highlight their significance in formulating novel potential anticancer therapeutics.

Therapeutic Potential of Centella asiatica and Its Triterpenes: A Review

Centella asiatica (also known as Centella asiatica (L.) Urb. or Gotu kola) is a traditional Chinese medicine with extensive medicinal value, which is commonly used in Southeast Asian countries. This study aimed to summarize the effects of C. asiatica and its main components on neurological diseases, endocrine diseases, skin diseases, cardiovascular diseases, gastrointestinal diseases, immune diseases, and gynecological diseases, as well as potential molecular mechanisms, to study the pathological mechanism of these diseases based on the changes at the molecular level. The results showed that C. asiatica and its triterpenoids had extensive beneficial effects on neurological and skin diseases, which were confirmed through clinical studies. They exhibited anti-inflammatory, anti-oxidative stress, anti-apoptotic effects, and improvement in mitochondrial function. However, further clinical studies are urgently required due to the low level of evidence and lack of patients.

RGD-decorated solid lipid nanoparticles enhance tumor targeting, penetration and anticancer effect of asiatic acid

Aim: Asiatic acid (AA) is a promising anticancer agent, however, its delivery to glioblastoma is a major challenge. This work investigates the beneficial therapeutic efficacy of RGD-conjugated solid lipid nanoparticles (RGD-SLNs) for the selective targeting of AA to gliblastoma. Materials & methods: AA-containing RGD-SLNs were prepared using two different PEG-linker size. Targetability and efficacy were tested using monolayer cells and spheroid tumor models. Results: RGD-SLNs significantly improved cytotoxicity of AA against U87-MG monolayer cells and enhanced cellular uptake compared with non-RGD-containing SLNs. In spheroid models, AA-containing RGD-SLNs showed superior control in tumor growth, improved cytotoxicity and enhanced spheroid penetration when compared with AA alone or non-RGD-containing SLNs. Conclusion: This study illustrates the potential of AA-loaded RGD-SLNs as efficacious target-specific treatment for glioblastoma.

Design, Synthesis, and Dual Evaluation of Quinoline and Quinolinium Iodide Salt Derivatives as Potential Anticancer and Antibacterial Agents

A series of novel quinoline and quinolinium iodide derivatives were designed and synthesized to discover potential anticancer and antibacterial agents. With regard to anticancer properties, in vitro cytotoxicities against three human cancer cell lines (A-549, HeLa and SGC-7901) were evaluated. The antibacterial properties against two strains, Escherichia coli (ATCC 29213) and Staphylococcus aureus (ATCC 8739), along with minimum inhibitory concentration (MIC) values were evaluated. The target alkyliodine substituted compounds exhibited significant antitumor and antibacterial activity, of which compound 8-((4-(benzyloxy)phenyl)amino)-7-(ethoxycarbonyl)-5-propyl-[1,3]dioxolo[4,5-g]quinolin-5-ium (12) was found to be the most potent derivative with IC₅₀ values of 4.45±0.88, 4.74±0.42, 14.54±1.96, and 32.12±3.66 against A-549, HeLa, SGC-7901, and L-02 cells, respectively, stronger than the positive controls 5-FU and MTX. Furthermore, compound 12 had the most potent bacterial inhibitory activity. The MIC of this compound against both E. coli and S. aureus was 3.125 nmol ⋅ mL^-1 , which was smaller than that against the reference agents amoxicillin and ciprofloxacin.

Asiatic Acid Interferes with Invasion and Proliferation of Breast Cancer Cells by Inhibiting WAVE3 Activation through PI3K/AKT Signaling Pathway

Objective

To explore the ability of asiatic acid to interfere with the invasion and proliferation of breast cancer cells by inhibiting WAVE3 expression and activation through the PI3K/AKT signaling pathway.

Methods

The MDA-MB-231 cells with strong invasiveness were screened by transwell assay, and plasmids with high expression of WAVE3 were constructed for transfection. The transfection effect and protein expression level of plasmids were verified by PCR and WB. The effects of asiatic acid on cell proliferation and invasion were investigated by flow cytometry. The xenografted tumor models in nude mice were established to study the antitumor activity of asiatic acid.

Results

Asiatic acid significantly inhibited the activity of MDA-MB-231 cells, and the expression level of WAVE3 increased significantly in the tissue of ductal carcinoma in situ and was lower than that in the metastasis group. After plasmid transfection, the mRNA and protein expression of WAVE3 increased significantly in the cells. Asiatic acid at different concentrations had an impact on cell apoptosis and invasion and could significantly inhibit the expression of WAVE3, P53, p-PI3K, p-AKT, and other proteins. The T/C(%) of asiatic acid (50 mg/kg) for MDA-MB-231(F10) xenografted tumor in nude mice was 46.33%, with a tumor inhibition rate of 59.55%. Asiatic acid could significantly inhibit the growth of MDA-MB-231 (F10) xenografted tumors in nude mice (p < 0.05).

Conclusions

Asiatic acid interferes with the ability of breast cancer cells to invade and proliferate by inhibiting WAVE3 expression and activation and the mechanism of action may be related to the PI3K/AKT signaling pathway.

Asiatic Acid, Extracted from Centella asiatica and Induces Apoptosis Pathway through the Phosphorylation p38 Mitogen-Activated Protein Kinase in Cisplatin-Resistant Nasopharyngeal Carcinoma Cells

Nasopharyngeal carcinoma (NPC) is an important issue in Asia because of its unique geographical and ethnic distribution. Cisplatin-based regimens are commonly the first-line used chemotherapy, but resistance and toxicities remain a problem. Therefore, the use of anticancer agents derived from natural products may be a solution. Asiatic acid (AA), extracted from Centella asiatica, was found to have anticancer activity in various cancers. The aim of this study is to examine the cytotoxic effect and mediated mechanism of AA in cisplatin-resistant NPC cells. The results shows that AA significantly reduce the cell viability of cisplatin-resistant NPC cell lines (cis NPC-039 and cis NPC-BM) in dose and time dependent manners caused by apoptosis through the both intrinsic and extrinsic apoptotic pathways, including altered mitochondrial membrane potential, activated death receptors, increased Bax expression, and upregulated caspase 3, 8, and 9. The Western blot analysis of AA-treated cell lines reveals that the phosphorylation of MAPK pathway proteins is involved. Further, the results of adding inhibitors of these proteins indicates that the phosphorylation of p38 are the key mediators in AA-induced apoptosis in cisplatin-resistant human NPC cells. This is the first study to demonstrate the AA-induced apoptotic pathway through the phosphorylation p38 in human cisplatin-resistant nasopharyngeal carcinoma. AA is expected to be another therapeutic option for cisplatin-resistant NPC because of the promising anti-cancer effect and fewer toxic properties.

Development of a multivalent acetylcholinesterase inhibitor via dynamic combinatorial chemistry

In this study, we report the generation of a polymer based dynamic combinatorial library (DCL) using aldehyde-functionalized linear poly(glycidol) and hydrazide derivatives as initial building blocks. In combination with tetrameric acetylcholinesterase (AChE), a certain type of amplified acylhydrazone side chain is identified and further used for the synthesis of a multivalent AChE inhibitor. The cytotoxicity and inhibition properties of the multivalent inhibitor are evaluated, and the results indicate superior bioactivity compared to the commercial reference Edrophonium chloride.

Secondary metabolites in plants: main classes, phytochemical analysis and pharmacological activities

Plants are an essential source of chemical compounds with different biological properties that man can use to his advantage. These substances are mainly produced as a result of chemical conversions of secondary metabolism. This article reviews the main classes of secondary metabolites that synthesize plants as well as their characteristics and their biological functions. Examples are provided for each of the classes. Emphasis is placed on the methods of extracting secondary metabolites and phytochemical screening, as well as on the main pharmacological activities described for the MS.

Asiatic Acid Attenuates Bone Loss by Regulating Osteoclastic Differentiation

Anti-resorptive agents like bisphosphonates have been widely used for the treatment of postmenopausal osteoporosis. However, their long-term safety and efficacy are still controversial. This study is to examine the effect of Asiatic acid (AA) in osteoclastic differentiation, and further to investigate its effect on bone quality in animals. Effect of AA on osteoclastic differentiation was measured by Tartrate-resistant acid phosphatase stain, bone resorption pit assays, and quantitative real-time polymerase chain reaction. Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and transforming growth factor-β (TGF-β) signaling were measured by western blot before and after AA treatment. Ovariectomized (OVX) wild-type or Smad7 partially knock out mice were used to evaluate the effects of AA on bone quality by micro-computed tomography, mechanical test, and histomorphometry. Results revealed a dose-dependent inhibitory effect of AA on osteoclastic differentiation. After AA treatment, Smad7 was upregulated, while NF-κB and TGF-β signaling were inhibited during osteoclastic differentiation. Results from animal study revealed that AA prevented bone from further loss caused by OVX and increased the mechanical properties of femur in wild-type animals. AA also prevented bone loss in the Smad7-deficient animals. When combining with OVX in the Smad7-deficient mice, AA could only partially preserve their bone mass. Taken together, we found that AA effectively inhibited osteoclastic differentiation and attenuated osteoporosis, which effects may be through TGF-β and NF-κB pathways. This study reveals that AA may be a potential anti-resorptive agent for postmenopausal osteoporosis.

Anti-Cancer Effects of Pristimerin and the Mechanisms: A Critical Review

As a quinonemethide triterpenoid extracted from species of the Celastraceae and Hippocrateaceae, pristimerin has been shown potent anti-cancer effects. Specifically, it was found that pristimerin can affect many tumor-related processes, such as apoptosis, autophagy, migration and invasion, vasculogenesis, and drug resistance. Various molecular targets or signaling pathways are also involved, such as cyclins, reactive oxygen species (ROS), microRNA, nuclear factor kappa B (NF-κB), mitogen-activated protein kinase (MAPK), and PI3K/AKT/mammalian target of rapamycin (mTOR) pathways. In this review, we will focus on the research about pristimerin-induced anti-cancer activities to achieve a deeper understanding of the targets and mechanisms, which offer evidences suggesting that pristimerin can be a potent anti-cancer drug.

Prussian blue nanosphere-embedded in situ hydrogel for photothermal therapy by peritumoral administration

To establish an injectable hydrogel containing Prussian blue (PB) nanospheres for photothermal therapy against cancer, PB nanospheres were prepared by one-pot synthesis and the thermosensitive Pluronic F127 was used as the hydrogel matrix. The PB nanospheres and the hydrogel were characterized by shape, particle size, serum stability, photothermal performance upon repeated 808 nm laser irradiation, as well as the rheological features. The effect of the PB nanospheres and the hydrogel were evaluated qualitatively and quantitatively in 4T1 mouse breast cancer cells. The retention, photothermal efficacy, therapeutic effects and systemic toxicity of the hydrogel were assessed in a tumor-bearing mouse model. The PB nanospheres had a diameter of about 150 nm and exhibited satisfactory serum stability, photo-heat convert ability and repeated laser exposure stability. The hydrogel encapsulation did not negatively influence the above features of the photothermal agent. The nanosphere-containing hydrogel showed a phase transition at body temperature and, as a result, a long retention time in vivo. The photothermal agent-embedded hydrogel displayed promising photothermal therapeutic effects in the tumor-bearing mouse model with little-to-no systemic toxicity after peritumoral administration.

Asiatic Acid Protects Dopaminergic Neurons from Neuroinflammation by Suppressing Mitochondrial Ros Production

This study sought to evaluate the effects of Asiatic acid in LPS-induced BV2 microglia cells and 1-methyl-4-phenyl-pyridine (MPP⁺)-induced SH-SY5Y cells, to investigate the potential anti-inflammatory mechanisms of Asiatic acid in Parkinson’s disease (PD). SH-SY5Y cells were induced using MPP⁺ to establish as an in vitro model of PD, so that the effects of Asiatic acid on dopaminergic neurons could be examined. The NLRP3 inflammasome was activated in BV2 microglia cells to explore potential mechanisms for the neuroprotective effects of Asiatic acid. We showed that Asiatic acid reduced intracellular production of mitochondrial reactive oxygen species and altered the mitochondrial membrane potential to regulate mitochondrial dysfunction, and suppressed the NLRP3 inflammasome in microglia cells. We additionally found that treatment with Asiatic acid directly improved SH-SY5Y cell viability and mitochondrial dysfunction induced by MPP⁺. These data demonstrate that Asiatic acid both inhibits the activation of the NLRP3 inflammasome by downregulating mitochondrial reactive oxygen species directly to protect dopaminergic neurons from, and improves mitochondrial dysfunction in SH-SY5Y cells, which were established as a model of Parkinson’s disease. Our finding reveals that Asiatic acid protects dopaminergic neurons from neuroinflammation by suppressing NLRP3 inflammasome activation in microglia cells as well as protecting dopaminergic neurons directly. This suggests a promising clinical use of Asiatic acid for PD therapy.

Asiatic acid enhances intratumor delivery and the antitumor effect of pegylated liposomal doxorubicin by reducing tumor-stroma collagen

Tumor-targeted drug delivery systems (Tt-DDSs) are proposed as a promising strategy for cancer care. However, the dense collagen network in tumors stroma significantly reduces the penetration and efficacy of Tt-DDS. In order to investigate the effect of asiatic acid (AA) on antitumor effect of pegylated liposomal doxorubicin (PLD) by attenuating stroma-collagen, colon cancer xenograft mice (SW620 cell line) were treated by PLD, AA, or combined regimes, respectively; the collagen levels were estimated by Sirius red/fast green dual staining and immunohistochemistry (IHC) staining; the intratumor exposure of doxorubicin was visualized by ex vivo fluorescence imaging and quantified by HPLC/MS analysis. In addition, the impact of AA on collagen synthesis of fibroblast cell (HFL-1) and cytotoxic effect of PLD and doxorubicin to cancer cell (SW620) were studied in vitro. In the presence of AA (4 mg/kg), the intratumor collagen level was restricted in vivo (reduced by 22%, from 4.14% ± 0.30% to 3.24% ± 0.25%, P = 0.051) and in vitro. Subsequently, doxorubicin level was increased by ~30%. The antitumor activity of PLD was significantly improved (57.3% inhibition of tumor growth and 44% reduction in tumor weight) by AA combination. Additionally, no significant improvement in cytotoxic effect of PLD or doxorubicin induced by AA was observed. In conclusion, AA is a promising sensitizer for tumor treatment by enhancing intratumor drug exposure via stromal remodeling.

Effect of asiatic acid on epithelial-mesenchymal transition of human alveolar epithelium A549 cells induced by TGF-β1

Asiatic acid (AA) is a pentacyclic triterpenoid isolated from Centella asiatica (L.) Urban that possesses significant antitumor activities. In the present study, the mechanism of AA on transforming growth factor-β1 (TGF-β1)-induced epithelial-mesenchymal transition (EMT) was investigated in the lung cancer cell line A549. To do so, cell morphological alterations were observed and recorded at different time periods. Cells treated with TGF-β1 were spindle-shaped and characterized as stromal cells, whereas AA-treated cells exhibited epithelial cell characteristics and increased intercellular adhesion. The MTT assay demonstrated that the high concentration of AA inhibited the viability of A549 cells treated with TGF-β. In addition, the wound healing and Transwell assays revealed that AA inhibited TGF-β1-induced invasion and migration of A549 cells. Furthermore, AA treatment increased the mRNA and protein expression levels of E-cadherin, and decreased the expression levels of snail family transcriptional repressor (Snail), N-cadherin, vimentin and β-catenin in TGF-β1-treated A549 cells. In conclusion, these results suggested that AA may inhibit TGF-β1-induced EMT in lung cancer through increased expression of E-cadherin, and inhibition of Snail, N-cadherin and vimentin expression.

Cembrane-type diterpenoids from the South China Sea soft coral Sarcophyton mililatensis

Eight cembrane-type diterpenoids, namely, (+)-(6R)-6-hydroxyisosarcophytoxide (1), (+)-(6R)-6-acetoxyisosarcophytoxide (2), (+)-17-hydroxyisosarcophytoxide (3), sarcomililatins A-D (4-7), and sarcomililatol (8), were isolated from the soft coral Sarcophyton mililatensis collected from Weizhou Island, Guangxi Autonomous Region, together with 2 known related analogues, (+)-isosarcophytoxide (9) and (+)-isosarcophine (10). The structures of these compounds were elucidated by a combination of detailed spectroscopic analyses, chemical methods, and comparison with reported data. The absolute configuration of compound 1 was established by the modified Mosher׳s method, while the absolute configurations of compounds 4 and 5 were assigned by electronic circular dichroism (ECD) spectroscopy and that of compound 8 was established by time-dependent density functional theory electronic circular dichroism (TD-DFT ECD) calculation. In in vitro bioassays, compound 9 displayed significant cytotoxicity against the human cancer cell lines human promyelocytic leukemia cells (HL-60) and human lung adenocarcinoma cells (A-549) with IC50 values of 0.78±0.21 and 1.26±0.80 μmol/L, respectively. Compounds 4 and 9 also showed moderate inhibitory effects on the TNFα-induced Nuclear factor kappa B (NF-κB, a therapeutical target in cancer) activation, showing IC50 values of 35.23±12.42 and 22.52±4.44 μmol/L, respectively.

Alantolactone induces apoptosis and suppresses migration in MCF‑7 human breast cancer cells via the p38 MAPK, NF‑κB and Nrf2 signaling pathways

Human breast cancer is a malignant type of cancer with high prevalence. In the present study, the anticancer effects of alantolactone, a sesquiterpene lactone, on the human breast cancer cell line MCF‑7 were investigated in vitro. The MCF‑7 cell morphology changed from diamond to round subsequent to treatment with alantolactone, and the cell viability reduced significantly compared with that of the control cells. Alantolactone induced apoptosis of MCF‑7 cells by regulating the protein expression levels of B‑cell lymphoma 2 (Bcl‑2), Bcl‑2‑associated X protein, p53, caspase‑3 and caspase‑12, which are associated with the apoptotic pathway, and suppressed colony formation and migration by regulating the protein expression of matrix metalloproteinase (MMP)‑2, MMP‑7 and MMP‑9. Cell signaling pathway analysis confirmed that alantolactone increased the phosphorylation of p38, and decreased the nuclear expression levels of p65 and nuclear factor erythroid 2‑related factor 2 (Nrf2), suggesting that the apoptosis‑promoting and migration‑suppressing effect of alantolactone may partially depend on regulating the p38 MAPK, NF‑κB and Nrf2 pathways. These results also suggested that alantolactone may become a potential therapeutic strategy for treating breast cancer.