Gambogic Acid and Its Role in Chronic Diseases

Elevated level of neuroserpin is an indication for the resistance to gambogic acid-induced apoptosis and oxidative stress in triple-negative breast cancer cells

Background

The triple-negative breast cancer (TNBC) subtype, characterized by loss of HER2, estrogen, and progesterone receptors, displays aggressive phenotype and poor prognosis compared to other BC subtypes. Since the TNBC cells are devoid of receptors, endocrine therapy is an ineffective option for TNBC patients, necessitating canonical chemotherapy strategies to treat TNBC. It is crucial to use alternative and natural agents to support chemotherapy in TNBC.

Objectives

To clarify the molecular mechanism of the tumorigenic effects of gambogic acid (GA) on TNBC cells with different epithelial character since GA has a wide spectrum of anticancer activity for most cancer types.

Methods

We determined the cytotoxic dose of GA incubation of TNBC cells (MDA-MB-231 and BT-20 cells) for 24 h. We performed the MTT test and toluidine blue (TB) staining protocol for TNBC cells. We analyzed E-cadherin, N-cadherin, Bax, and neuroserpin mRNAs in both cells by qPCR. We evaluated apoptosis using DAPI staining and assessed the ROS using the 2',7'-dichlorofluorescin diacetate (DCFH-DA) method.

Results

We determined the IC50 concentrations of GA in MDA-MB-231 and BT-20 cells to be 315.8 nM and 441.8 nM, respectively. TB staining showed that BT-20 cells survive at excessive cytotoxic doses of GA, while most of the MDA-MB-231 cells were killed. Also, we found that BT-20 cells are more resistant to GA-induced apoptosis and oxidative stress than the MDA-MB-231 cells. qPCR results showed that GA upregulated neuroserpin, an oxidative stress-relieving factor in the BT-20 cells, but not in the MDA-MB-231 cells.

Conclusions

The elevated level of neuroserpin could be a predictive marker to determine the development of resistance to chemotherapeutic agents.

Therapeutic potential of traditional Chinese medicine for interstitial lung disease

ETHNOPHARMACOLOGICAL RELEVANCE

Interstitial lung disease (ILD) is a chronic lung dysfunction disease with a poor prognosis and poor recovery. The clinically used therapeutic drugs, such as glucocorticoids and immunosuppressants, have no significant therapeutic effect and are accompanied with severe side effects. In recent years, considerable progress has been made in exploring and applying natural herb components for treating ILD. Traditional Chinese Medicine (TCM) possesses innate, non-toxic characteristics and offers advantages in preventing and treating pulmonary ailments. However, a comprehensive study of TCM on ILD therapy has not yet been reviewed.

AIM OF THE REVIEW

This review aimed to provide a comprehensive summary of the monomer components, total extracts, and prescriptions of TCM for ILD therapy, elucidating their molecular mechanisms to serve as a reference in treating ILD.

MATERIALS AND METHODS

The literature information was searched in the PubMed, Web of Science databases. The search keywords included 'interstitial lung disease', 'lung fibrosis' or 'pulmonary fibrosis', and 'traditional Chinese medicine', 'traditional herbal medicine', or 'herb medicine'.

RESULTS

The active components of single herbs, such as alkaloids, flavonoids, terpenoids, phenols, and quinones, have potential therapeutic effects on ILD. The active extracts and prescriptions were also summarized and analyzed. The herbs, Glycyrrhiza uralensis Fisch. (Gancao), Astragalus membranaceus Fisch. Bunge. (Huangqi) and Angelicasinensis (Oliv.) Diels (Danggui), play significant roles in the treatment of ILD. The mechanisms involve the inhibition of inflammatory factor release, anti-oxidative injury, and interference with collagen production, etc. CONCLUSION: This review examines the therapeutic potential of TCM for ILD and elucidates its molecular mechanisms, demonstrating that mitigating inflammation and oxidative stress, modulating the immune system, and promoting tissue repair are efficacious strategies for ILD therapy. The depth research will yield both theoretical and practical implications.

Influencing factors of falls among older adults in Chinese retirement institutions: A systematic review and meta-analysis

BACKGROUND

The incidence of falling has always been high among the elderly, and it was easy to cause injuries to the elderly and seriously affect their quality of life. There were many studies have been conducted on risk factors affecting the fall of the elderly, but the results widely, retirement institutions as a gathering place for the elderly, there was currently no comprehensive analysis of the factors related to elderly falls in pension institutions. This study aimed to explore the influencing factors of falls among older adults in Chinese nursing homes.

METHODS

Chinese and English databases were searched for literature published from database inception to 5 April 2023 on the influencing factors of falls among older adults in Chinese nursing homes. Two reviewers independently screened articles, extracted data, and assessed the quality of the included studies. Meta-analysis was performed using RevMan 5.4 software.

RESULTS

Eleven studies involving 3503 participants were included in the meta-analysis. The pooled estimate of falls among older adults in Chinese nursing homes was 32% [95% confidence interval (95%CI) (24.0%, 39.0%)]. The main influencing factors for falls among older adults in Chinese nursing homes were age (Odds Ratio (OR) = 1.53), gender (OR = 5.50), visual impairment (OR = 2.30), sedative-hypnotics (OR = 2.36), fear of falling (OR = 2.95), hypertension (OR = 3.72), static balance (OR = 2.02), three or more chronic diseases (OR = 5.63), cognitive status (OR = 2.64), walking aid use (OR = 1.98), fall-related chronic diseases (OR = 2.48), self-awareness of abilities (OR = 2.43), and frequent reminders for fall prevention (OR = 0.10).

CONCLUSION

Falls among older adults in Chinese nursing homes were common, and there were many influencing factors. Timely screening and intervention should be implemented to reduce the adverse consequences of falls on older adults.

TRIAL REGISTRATION

Registration number: CRD42023421099.

Investigations into the antibacterial effects and potential mechanism of gambogic acid and neogambogic acid

The growing threat of antibiotic-resistant bacterial infections to public health necessitates the development of novel antibacterial agents. Inhibiting bacterial cell wall synthesis has remained a key focus for antibiotic development. Our search for inhibitors of undecaprenyl diphosphate synthase (UPPS), an essential enzyme required for bacterial cell wall formation, revealed that two primary components of gamboge, gambogic acid (GA) and neogambogic acid (NGA), significantly inhibited the activity of Enterococcus faecalis UPPS (EfaUPPS) with the half maximal inhibitory concentrations (IC₅₀) of 3.08 μM and 3.07 μM, respectively. In the in vitro antibacterial assay, both GA and NGA also exhibited inhibitory activities against E. faecalis with the minimal inhibitory concentrations (MICs) of 2 μg/mL. Using microscale thermophoresis, molecular docking, and enzymatic assays, we further confirmed that GA and NGA occupy the substrate binding pocket of EfaUPPS with micro-molar binding affinity, preventing the natural substrates farnesyl diphosphate (FPP) from entering. Mutagenesis analysis revealed that L91 and L146 are two key residues in the binding between GA/NGA and UPPS. Furthermore, we also demonstrated that GA and NGA can improve E. faecalis-induced undesirable inflammation in a mouse infection model. Taken together, our findings provide a basis for structural optimization of GA/NGA to develop improved antibiotic leads and enhance treatment success rates in clinical practice.

Gambogic acid and juglone inhibit RNase P through distinct mechanisms

The first step in transfer RNA (tRNA) maturation is the cleavage of the 5' end of precursor tRNA (pre-tRNA) catalyzed by ribonuclease P (RNase P). RNase P is either a ribonucleoprotein complex with a catalytic RNA subunit or a protein-only RNase P (PRORP). In most land plants, algae, and Euglenozoa, PRORP is a single-subunit enzyme. There are currently no inhibitors of PRORP for use as tools to study the biological function of this enzyme. Therefore, we screened for compounds that inhibit the activity of a model PRORP from A. thaliana organelles (PRORP1) using a high throughput fluorescence polarization cleavage assay. Two compounds, gambogic acid and juglone (5-hydroxy-1,4-naphthalenedione) that inhibit PRORP1 in the 1 μM range were identified and analyzed. We found these compounds similarly inhibit human mtRNase P, a multisubunit protein enzyme and are 50-fold less potent against bacterial RNA-dependent RNase P. Our biochemical measurements indicate that gambogic acid is a rapid-binding, uncompetitive inhibitor targeting the PRORP1-substrate complex, while juglone acts as a time-dependent PRORP1 inhibitor. Additionally, X-ray crystal structures of PRORP1 in complex with juglone demonstrate the formation of a covalent complex with cysteine side chains on the surface of the protein. Finally, we propose a model consistent with the kinetic data that involves juglone binding to PRORP1 rapidly to form an inactive enzyme-inhibitor complex and then undergoing a slow step to form an inactive covalent adduct with PRORP1. These inhibitors have the potential to be developed into tools to probe PRORP structure and function relationships.

Neogambogic acid relieves myocardial injury induced by sepsis via p38 MAPK/NF-κB pathway

Sepsis-associated myocardial injury, an invertible myocardial depression, is a common complication of sepsis. Neogambogic acid is an active compound in garcinia and exerts anthelmintic, anti-inflammatory, and detoxification properties. The role of neogambogic acid in sepsis-associated myocardial injury was assessed. Firstly, mice were pretreated with neogambogic acid and then subjected to lipopolysaccharide treatment to induce sepsis. Results showed that lipopolysaccharide treatment induced up-regulation of biomarkers involved in cardiac injury, including lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB), and troponin I (cTnI). However, pretreatment with neogambogic acid reduced levels of LDH, CK-MB, and cTnI, and ameliorated histopathological changes in the heart tissues of septic mice. Secondly, neogambogic acid also improved cardiac function in septic mice through reduction in left ventricular end-diastolic pressure, and enhancement of ejection fraction, fractional shortening, and left ventricular systolic mean pressure. Moreover, neogambogic acid suppressed cardiac apoptosis and inflammation in septic mice and reduced cardiac fibrosis. Lastly, protein expression of p-p38, p-JNK, and p-NF-κB in septic mice was decreased by neogambogic acid. In conclusion, neogambogic acid exerted anti-apoptotic, anti-fibrotic, and anti-inflammatory effects in septic mice through the inactivation of MAPK/NF-κB pathway.

Local delivery of gambogic acid to improve anti-tumor immunity against oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) accounts for nearly 90% of oral cavity malignancies. However, despite significant advances in the last four decades, little improvement has been achieved in the overall survival rates for OSCC patients. While gambogic acid (GA) is a potential candidate compound for treating a variety of malignancies, its anti-cancer impact on OSCC has not to be completely investigated. The tumor immune microenvironment (TIME) has been proven to play a crucial role in the prognosis of cancer patients. Although there are few reports on the T cell activation effect of GA, the regulation of GA on the TIME of OSCC has barely been studied yet. In this study, GA was applied to treat OSCC-bearing mice through in situ controlled release. First, GA-loaded mPEG₂₀₀₀-PCL micelles (GA-MIC) were prepared by the thin-film hydration method to improve the aqueous dispersibility of GA. Second, poly(D, l-lactide)-poly(ethylene glycol)-poly(D, l-lactide) (PLEL) was synthesized for thermosensitive hydrogel preparation. Third, GA-MIC was mixed with PLEL to form an injectable therapeutic hydrogel (GA-MIC-GEL). The anti-tumor and TIME regulation effects of GA-MIC-GEL on tumor-bearing mice were further examined. The results showed that the thermosensitive GA-MIC-GEL with sensitive sol-gel transition characteristics could form hydrogel at 37 °C within 24 s, facilitating the local delivery and sustained GA release. Biochemical, hematological, and pathological analysis proved that GA-MIC-GEL has good biological safety. Moreover, GA-MIC-GEL promoted an obvious regression of both primary and distant tumors on the OSCC mouse models. Mechanically, GA-MIC-GEL down-regulated the expression of PD-1, increased the frequency of cytotoxic T cells and reduced the immunosuppressive cellular components, which boosted the anti-tumor immunity of OSCC-bearing mice. The constructed thermosensitive hydrogel for local delivery of GA has provided a safe and effective strategy with great potential for OSCC therapy.

Gambogic Acid Induces HO-1 Expression and Cell Apoptosis through p38 Signaling in Oral Squamous Cell Carcinoma

Gambogic acid (GA), a natural and bioactive compound from the gamboge resin, has been reported to exhibit many oncostatic activities against several types of malignancies. However, its effects on the progression of oral squamous cell carcinoma (OSCC) remain largely unexplored. To fill this gap, we investigated the anticancer role of GA and molecular mechanisms underlying GA's actions in combating oral cancer. We found that GA negatively regulated the viability of OSCC cells, involving induction of the sub-G1 phase and cell apoptosis. In addition, a specific signature of apoptotic proteome, such as upregulation of heme oxygenase-1 (HO-1) and activation of caspase cascades, was identified in GA-treated OSCC. Moreover, such induction of HO-1 expression and caspase cleavage by GA was significantly diminished through the pharmacological inhibition of p38 kinase. In conclusion, these results demonstrate that GA promotes cell apoptosis in OSCC, accompanied with the activation of a p38-dependent apoptotic pathway. Our findings provide potential avenues for the use of GA with high safety and therapeutic implications in restraining oral cancer.

A Gambogic Acid-Loaded Delivery System Mediated by Ultrasound-Targeted Microbubble Destruction: A Promising Therapy Method for Malignant Cerebral Glioma

Background

Purpose

Methods

Results

Conclusion

Nuclear Targeted Peptide Combined With Gambogic Acid for Synergistic Treatment of Breast Cancer

As a natural compound, gambogic acid (GA) emerged a shining multi-target antitumor activity in a variety of tumors. Whereas its poor solubility and non-specific effect to tumor blocked the clinical application of this drug. Herein, we reported a simple and effective strategy to construct liposome modified with nuclear targeted peptide CB5005N (VQRKRQKLMPC) via polyethylene glycol (PEG) linker to decrease the inherent limitations of GA and promote its anti-tumor activity. In this study, liposomes were prepared by thin film hydration method. The characterization of formulations contained particle size, Zeta potential, morphology and encapsulation efficiency. Further, in vitro cytotoxicity and uptake tests were investigated by 4T1 and MDA-MB-231 cells, and nuclear targeting capability was performed on MDA-MB-231 cells. In addition, the in vivo antitumor effect and biological distribution of formulations were tested in BALB/c female mice. The GA-loaded liposome modified by CB5005N showed small size, good uniformity, better targeting, higher anti-tumor efficiency, better tumor inhibition rate and lower toxicity to normal tissues than other groups. In vitro and in vivo research proved that CB5005N-GA-liposome exhibited excellent anti-tumor activity and significantly reduced toxicities. As a result, CB5005N-GA-liposome nano drug delivery system enhanced the tumor targeting and antitumor effects of GA, which provided a basis for its clinical application.

Gambogic acid: A shining natural compound to nanomedicine for cancer therapeutics

The United States Food and Drug Administration has permitted number of therapeutic agents for cancer treatment. Most of them are expensive and have some degree of systemic toxicity which makes overbearing in clinical settings. Although advanced research continuously applied in cancer therapeutics, but drug resistance, metastasis, and recurrence remain unanswerable. These accounts to an urgent clinical need to discover natural compounds with precisely safe and highly efficient for the cancer prevention and cancer therapy. Gambogic acid (GA) is the principle bioactive and caged xanthone component, a brownish gamboge resin secreted from the of Garcinia hanburyi tree. This molecule showed a spectrum of biological and clinical benefits against various cancers. In this review, we document distinct biological characteristics of GA as a novel anti-cancer agent. This review also delineates specific molecular mechanism(s) of GA that are involved in anti-cancer, anti-metastasis, anti-angiogenesis, and chemo-/radiation sensitizer activities. Furthermore, recent evidence, development, and implementation of various nanoformulations of gambogic acid (nanomedicine) have been described.

Transcriptional Analysis of the Effects of Gambogic Acid and Neogambogic Acid on Methicillin-Resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) infection is a major threat to human health, as this bacterium has developed resistance to a variety of conventional antibiotics. This is especially true of MRSA biofilms, which not only exhibit enhanced pathogenicity but also are resistant to most antibiotics. In this work, we demonstrated that two natural products with antitumor activity, namely, gambogic acid (GA) and neogambogic acid (NGA), have significant inhibitory activity toward MRSA. GA and NGA can not only effectively inhibit planktonic MRSA strains in vivo and in vitro, but also have strong inhibitory effects on MRSA biofilms formation. By transcriptome sequencing, Q-RT-PCR and PRM, we found that GA and NGA could reduce the expression of S. aureus virulence factors by inhibiting the saeRS two-component, thus achieving inhibition of MRSA. We found that GA and NGA had anti-MRSA activity in vivo and in vitro and identified saeRS to be the target, indicating that saeRS inhibitors may be used to treat biofilm-related infections.

Next-Generation Noncompetitive Nanosystems Based on Gambogic Acid: In silico Identification of Transferrin Receptor Binding Sites, Regulatory Shelf Stability, and Their Preliminary Safety in Healthy Rodents

A major challenge in drug delivery is to enhance the transport of drugs across biological barriers, such as the small intestine, the blood-brain barrier, and the blood-retinal/ocular barrier, and to effectively reach the site of action while minimizing the systemic impact. In recent years, piggybacking cell surface receptors have been considered a viable strategy for active drug delivery across the biological barriers. However, the ligands used to target drugs to plasma membrane receptors often have to compete against endogenous ligands, thereby limiting their binding to the cell surface and their transport across barriers. To address this problem, gambogic acid (GA) was identified as a noncompetitive ligand specific to the transferrin receptor (TfR), a receptor present on various barriers. However, the binding sites of the GA on TfR remain unknown, an essential step toward establishing structure-activity relationships. In silico binding site prediction tools, blind docking, and molecular docking simulation confirm that the GA binding site on the TfR is independent of the transferrin-bound iron binding sites. The GA-conjugated polyesters were processed into nanoparticles suitable for drug delivery applications that possess excellent storage stability under regulatory conditions. Traditionally, GA has been used as an anticancer compound that warrants safety assessment. The preliminary studies in healthy rodents on 10-repeated oral doses show no adverse effects. This work will generate paradigm shifting, new knowledge in the field of nanomedicines using unique noncompetitive nanosystems that do not compete with endogenous transferrin.

Targeting oncogenic transcription factors by polyphenols: A novel approach for cancer therapy

Inflammation is one of the major causative factor of cancer and chronic inflammation is involved in all the major steps of cancer initiation, progression metastasis and drug resistance. The molecular mechanism of inflammation driven cancer is the complex interplay between oncogenic and tumor suppressive transcription factors which include FOXM1, NF-kB, STAT3, Wnt/β- Catenin, HIF-1α, NRF2, androgen and estrogen receptors. Several products derived from natural sources modulate the expression and activity of multiple transcription factors in various tumor models as evident from studies conducted in cell lines, pre-clinical models and clinical samples. Further combination of these natural products along with currently approved cancer therapies added an additional advantage and they considered as promising targets for prevention and treatment of inflammation and cancer. In this review we discuss the application of multi-targeting natural products by analyzing the literature and future directions for their plausible applications in drug discovery.

Therapeutic potential of gambogic acid, a caged xanthone, to target cancer

Natural compounds have enormous biological and clinical activity against dreadful diseases such as cancer, as well as cardiovascular and neurodegenerative disorders. In spite of the widespread research carried out in the field of cancer therapeutics, cancer is one of the most prevalent diseases with no perfect treatment till date. Adverse side effects and the development of chemoresistance are the imperative limiting factors associated with conventional chemotherapeutics. For this reason, there is an urgent need to find compounds that are highly safe and efficacious for the prevention and treatment of cancer. Gambogic acid (GA) is a xanthone structure extracted from the dry, brownish gamboge resin secreted from the Garcinia hanburyi tree in Southeast Asia and has inherent anti-cancer properties. In this review, the molecular mechanisms underlying the targets of GA that are liable for its effective anti-cancer activity are discussed that reveal the potential of GA as a pertinent candidate that can be appropriately developed and designed into a capable anti-cancer drug.

Gambogic acid inhibits spinal cord injury and inflammation through suppressing the p38 and Akt signaling pathways

Gamboge is the dry resin secreted by Garcinia hanburyi Hook.f, with the function of promoting blood circulation, detoxification, hemostasis and killing insects, used for the treatment of cancer, brain edema and other diseases. Gambogic acid is the main effective constituent of Gamboge. The present study investigated the protective effects of gambogic acid on spinal cord injury (SCI) and its anti‑inflammatory mechanism in an SCI model in vivo. Basso, Beattie and Bresnahan (BBB) testing was used to detect the protective effects of gambogic acid on nerve function of SCI rats. The water content of the spinal cord was used to analyze the protective effects of gambogic acid on the damage of SCI. Treatment with gambogic acid effectively improved BBB scores and inhibited water content of the spinal cord in SCI rats. Also, gambogic acid significantly reduced inflammatory cytokines levels of [tumor necrosis factor‑α, interleukin (IL)‑6, IL‑12 and IL‑1β] and oxidative stress (malondialdehyde, superoxide dismutase, glutathione and glutathione‑peroxidase) factors, and suppressed receptor activator of nuclear factor κB ligand, phosphorylated p38 protein expression and toll‑like receptor 4/nuclear factor‑κB pathway activation, and increased phosphatidylinositol 3‑kinase/protein kinase B (Akt) pathway activation in SCI rats. These results provide evidence that gambogic acid inhibits SCI and inflammation through suppressing the p38 and Akt signaling pathways.

Exploration of acute genotoxic effects and antigenotoxic potential of gambogic acid using Allium cepa assay

The plant derived xanthanoid gambogic acid (GA) is well known for its anticancer activity. To date, biological actions of GA on plant system have not been reported. In the present study, we evaluated the potential acute genotoxic activity of GA, and its antigenotoxic potential against H₂O₂ induced genetic damage using Allium cepa root chromosomal aberration assay under hydroponic conditions. There was a significant decrease in the percentage of mitotic index/prophase index with the increase in clastogenicity percentage in a dose and time-dependent manner when Allium cepa bulbs were exposed to GA at 0.1 mM and 1 mM concentration for 1 h, 2 h, and 4 h. Total genomic DNA integrity analyzed by agarose gel electrophoresis and cell viability revealed pronounced DNA degradation and loss of viability when treated with 1  mM GA for 4 h. In situ histochemical localization by Schiff's staining and 3, 3-diaminobenzidine confirmed increased levels of lipid peroxide and H₂O₂ in GA treated roots respectively. Scanning electron microscopy and FT-IR suggested surface damage and biomolecular intervention of GA in root cells. In addition, possible antigenotoxic effect of GA at lower concentration was explored by employing standard assays using H₂O₂. We observed a higher percentage of nuclear lesions upon treatment with 3% H₂O₂ (97.21 ± 0.76) that reduced significantly after modulatory treatment with 0.01 mM GA (70.44 ± 4.42). The results suggest that GA is a Janus-faced compound as it demonstrates a genotoxic activity at higher doses and genoprotective action at lower precise doses.