Modulation of the triggered apoptosis by nano emodin transfersome-mediated sonodynamic therapy on head and neck squamous cell carcinoma cell lines

Advances in nano drug delivery systems for enhanced efficacy of emodin in cancer therapy

Cancer remains one of the leading causes of death worldwide, highlighting the urgent need for novel antitumor drugs. Natural products have long been a crucial source of anticancer agents. Among these, emodin (EMO), a multifunctional anthraquinone compound, exhibits significant anticancer effects but is hindered in clinical applications by challenges such as low solubility, rapid metabolism, poor bioavailability, and off-target toxicity. Nano drug delivery systems offer effective strategies to overcome these limitations by enhancing the solubility, stability, bioavailability, and targeting ability of EMO. While substantial progress has been made in developing EMO-loaded nanoformulations, a comprehensive review on this topic is still lacking. This paper aims to fill this gap by providing an overview of recent advancements in nanocarriers for EMO delivery and their anticancer applications. These carriers include liposomes, nanoparticles, polymeric micelles, nanogels, and others, with nanoparticle-based formulations being the most extensively explored. Nanoformulations encapsulating EMO have demonstrated promising therapeutic results against various cancers, particularly breast cancer, followed by liver and lung cancers. We systematically summarize the preparation methods, materials, and physicochemical properties of EMO-loaded nanopreparations, underscoring key findings on how nanotechnology improves the anticancer efficacy of EMO. This review provides valuable insights for researchers engaged in developing nano delivery systems for anticancer drugs.

Nuclease-Mimetic Nanomaterials: From Fundamentals to Bioapplications

With the rapid development of nanozymes and nanomedicine, designing novel nanostructures directly acting on deoxyribonucleic acid (DNA) has great therapeutic potential because DNA is the carrier of genetic information and plays a vital role on life activities of the organism. Specifically, DNA cleavage is an important step in most of these DNA engineering technologies. While nucleases play crucial roles in the cell metabolism by efficient DNA cutting, the practical applications of natural nucleases suffer from some intrinsic shortcomings such as high cost and intolerance to harsh environments. In the past 20 years, great varieties of engineered nanostructures with DNA cleavage (nuclease-mimetic nanomaterials, abbreviated as nuclease mimics) have been developed rapidly and widely used in biomedical fields. In view of the significant progress of nuclease-mimetic nanomaterials, the possible DNA cleavage mechanism mediated by nuclease-mimetic nanomaterials is systematically discussed in this review, and the classification of nuclease-mimetic nanomaterials is illustrated. Their potential biomedical applications, especially in anti-biofilms and cancer treatment, are also comprehensively summarized. Finally, the current opportunities and challenges are discussed to stimulate the research of understanding and development of nuclease-mimetic nanomaterials.

Assessing the physico-mechanical, anti-bacterial, and anti-demineralization properties of orthodontic resin composite containing different concentrations of photoactivated zinc oxide nanoparticles on Streptococcus mutans biofilm around ceramic and metal orthodontic brackets: An ex vivo study

BACKGROUND AND PURPOSE

The aim of this study was to evaluate the physico-mechanical, anti-bacterial, and anti-demineralization properties of orthodontic resin composite containing photoactivated zinc oxide nanoparticles (ZnONPs) on Streptococcus mutans biofilm around ceramic and metal brackets.

MATERIAL AND METHODS

Following the minimum inhibitory concentration (MIC) determination for ZnONPs, shear bond strength (SBS) was tested for composites containing different concentrations of ZnONPs. The chosen concentration was used to evaluate the microleakage, anti-bacterial, and anti-demineralization properties.

RESULTS

Adding 50μg/mL of ZnONPs to the orthodontic composite did not negatively affect its physico-mechanical properties. ZnONPs (50μg/mL)-mediated aPDT and 0.2% chlorhexidine significantly (P=0.000) reduced S. mutans biofilms compared to the phosphate-buffered saline (PBS) groups (metal/PBS=7.47±0.7×106, and ceramic/PBS=7.47±0.7×106), with the lowest colony count observed in these groups (metal/chlorhexidine=1.06±0.4×105, ceramic/chlorhexidine=1±0.2×105, metal/ZnONPs-mediated aPDT=1.33±0.3×105, and ceramic/ZnONPs-mediated aPDT=1.2±0.3×105). Sodium fluoride varnish and ZnONPs-mediated aPDT showed the highest efficacy in anti-demineralization and significantly improving the enamel surface microhardness compared to the artificial saliva, especially in ceramic bracket groups (524.17±42.78N and 441.00±29.48N, 394.17±46.83N, P=0.000, and P=0.003, respectively).

CONCLUSION

ZnONPs (50μg/mL)-mediated aPDT effectively inhibited S. mutans biofilm and promoted anti-demineralization without adverse effects on the physico-mechanical properties of the composite resin. These results suggest the potential of this method in preventing white spot lesions during orthodontic treatment.

In vitro and in vivo investigation of the inhibitory effects of Sinoporphyrin sodium-mediated Sonodynamic therapy on human oral squamous cell carcinoma

OBJECTIVE

Sonodynamic therapy (SDT) is an innovative, non-invasive approach to cancer treatment, by using low-intensity ultrasound to trigger the activation of sonosensitizers localized within cancerous cells. This current study aimed to explore the therapeutic efficacy of a new sonosensitizer, Sinoporphyrin Sodium (DVDMS), under ultrasound irradiation, against oral squamous cell carcinoma (OSCC)-derived SCC-154 cells, both in vitro and in vivo.

METHODS

Fluorescence spectra, cytotoxicity assessments, uptake mechanisms, and subcellular distributions of DVDMS within the SCC-154 cell line were detected. Additionally, the study comprehensively assessed the antitumor effect, oxidative stress responses, apoptosis, apoptosis-related proteins, autophagic processes, and ultrastructural changes in SCC-154 cells, both in vitro and in vivo, subsequent to treatment with low-intensity ultrasound (at 1.0 MHz, 1 W/cm2 in vitro and 3 W/cm2 in vivo) in conjunction with DVDMS also being examined.

RESULTS

The findings indicate that SCC-154 cells exhibit heightened sensitivity to DVDMS compared to SAS and HSC-3 cell lines. Within SCC-154 cells, DVDMS primarily localizes within the mitochondria and lysosomes. DVDMS-based SDT significantly increased the intracellular levels of reactive oxygen species (ROS), induced morphological changes such as mitochondrial swelling and formation of autolysosomes, and exhibited a notable dose-dependent reduction in cell viability in vitro. Also, DVDMS-SDT demonstrated significant inhibition of xenograft growth without discernible adverse effects. Mechanistically, DVDMS-SDT upregulated Bax expression while downregulating Bcl-2 expression, which led to the Bax/Bcl-2 ratio and induced autophagy.

CONCLUSION

DVDMS-SDT triggers mitochondrial-dependent apoptosis in SCC-154 cells, unlike 5-ALA and protoporphyrin IX (PpIX). Also, the combination of DVDMS with ultrasound stimulation induces autophagy, with the onset of autophagic processes preceding apoptosis.

Study on the Hepatotoxicity of Emodin and Its Application in the Treatment of Liver Fibrosis

Emodin (EMO) is an anthraquinone compound derived from Rheum palmatum L., which has rich pharmacological activity. However, studies have shown that EMO may cause hepatotoxicity. In this study, EMO was combined with tetrandrine and prepared as lipid nanoparticles (E-T/LNPs). The anti-liver fibrosis activity of EMO before and after formulation was evaluated by zebrafish and mice. In addition, the toxicity of EMO and E-T/LNPs was compared and the toxicity-efficacy concentrations of E-T/LNPs in zebrafish were verified. E-T/LNPs are morphologically stable (particle size within 100 nm), have high encapsulation efficiency and good stability, and are capable of long-lasting slow release in vitro. The combination and preparation can reduce the toxicity and enhance the effect of EMO, and increase the toxicity and effect concentration of E-T/LNPs in vivo. In a short period, low doses of E-T/LNPs can be used for the treatment of liver fibrosis; high doses of E-T/LNPs cause toxicity in vivo. Immunohistochemistry showed that E-T/LNPs inhibited hepatic fibrosis by downregulating the levels of IL-1β and TGF-β. Based on the advantages of combination therapy and nanotechnology, it can play a role in reducing the toxicity and increasing the efficacy of EMO in the treatment of liver fibrosis.

Neuroprotective, Anti-Inflammatory and Antifibrillogenic Offerings by Emodin against Alzheimer's Dementia: A Systematic Review

Background: Alzheimer's disease (AD) is among the major causes of dementia in the elderly and exerts tremendous clinical, psychological and socio-economic constraints. Currently, there are no effective disease-modifying/retarding anti-AD agents. Emodin is a bioactive phytochemical with potent multimodal anti-inflammatory, antioxidant, and antifibrillogenic properties. In particular, emodin may result in significant repression of the pathogenic mechanisms underlying AD. The purpose of this review is to accumulate and summarize all the primary research data evaluating the therapeutic actions of emodin in AD pathogenesis. Methodology: The search, selection, and retrieval of pertinent primary research articles were systematically performed using a methodically designed approach. A variety of keyword combinations were employed on online scholarly web-databases. Strict preset inclusion and exclusion criteria were used to select the retrieved studies. Data from the individual studies were summarized and compiled into different sections, based upon their findings. Results: Cellular and animal research indicates that emodin exerts robust multimodal neuroprotection in AD. While emodin effectively prevents tau and amyloid-beta (Aβ) oligomerization, it also mitigates their neurotoxicity by attenuating neuroinflammatory, oxidative, and bioenergetic defects. Evidences for emodin-mediated enhancements in memory, learning, and cognition were also found in the literature. Conclusion: Emodin is a potential anti-AD dietary supplement; however, further studies are warrantied to thoroughly understand its target players and mechanisms. Moreover, human clinical data on emodin-mediated amelioration of AD phenotype is largely lacking, and must be addressed in the future. Lastly, the safety of exogenously supplemented emodin must be thoroughly evaluated.

Role of Cathepsin B Expression in Oral Squamous Cell Carcinoma: A Comprehensive Review

This comprehensive review delves into the intricate landscape of oral squamous cell carcinoma (OSCC) by examining the role of cathepsin B expression in its pathogenesis. OSCC, a prevalent and clinically significant oral malignancy, poses a considerable global health burden, necessitating a thorough exploration of its underlying molecular mechanisms. Cathepsin B, a lysosomal cysteine protease, emerges as a critical player in OSCC, influencing tumour initiation, invasion, and metastasis. The review begins with a brief overview of OSCC, emphasizing its epidemiological and clinical features, followed by exploring the significance of studying cathepsin B expression in this context. In the manuscript, the structure and function of cathepsin B are elucidated, providing a foundation for understanding its aberrant expression in OSCC. Clinical studies revealing correlations with tumour grade and stage, along with prognostic significance, are scrutinized, offering insights into the potential diagnostic and prognostic utility of cathepsin B. The biological functions of cathepsin B in OSCC, including its impact on tumour invasion and modulation of apoptosis, are comprehensively discussed. The Therapeutic Implications section explores targeting cathepsin B as a potential strategy, emphasizing the need for future research to overcome associated challenges. In the Conclusion section, the review synthesizes key findings, delineates implications for future research, and highlights the potential impact of cathepsin B on OSCC diagnosis and treatment, contributing to the ongoing efforts to advance our understanding of this complex malignancy, which is associated with a high mortality rate and improve clinical outcomes.

Enhancement of hypericin nanoparticle-mediated sonoinduced disruption of biofilm and persister cells of Streptococcus mutans by dermcidin-derived peptide DCD-1L

BACKGROUND

Streptococcus mutans is considered a major significant contributor to dental caries and its effective removal is difficult due to the formation of biofilm. Therefore, the development of adjuvant therapeutic strategies with anti-biofilm properties is a promising approach. In the present study, we examined the effect of dermcidin-derived peptide DCD-1 L on the antibacterial activity of hypericin nanoparticle (HypNP)-mediated antimicrobial sonodynamic therapy (aSDT) against persister cells growing- and biofilm cultures of S. mutans.

MATERIALS AND METHODS

Following synthesis and confirmation of HypNP, the fractional inhibitory concentration (FIC) index of HypNP and DCD-1 L was determined by checkerboard assay. Cellular uptake of HypNP-DCD-1 L and generation of endogenous reactive oxygen species (ROS) were assessed and followed by the determination of antimicrobial sonoactivity of HypNP-DCD-1 L against persister cells growing- and biofilm cultures of S. mutans. The water-insoluble extracellular polysaccharide (EPS) and expression of the gtfD, comDE, and smuT genes were then evaluated in persister cells growing- and biofilm cultures of S. mutans.

RESULTS

There was a synergistic activity in the combination of HypNP and DCD-1 L against S. mutans with an FIC index value of 0.37. The HypNP-DCD-1L-mediated aSDT also displayed the highest cellular uptake and endogenous ROS generation by bacterial cells. When biofilm and persister cells of S. mutans were treated with HypNP-DCD-1 L and subsequently exposed to ultrasound waves, 5.1 log and 3.8 log reductions, respectively, in bacterial numbers were observed (P<0.05). According to the data, EPS in both persister cells growing- and biofilm cultures of S. mutans were significantly decreased after exposure to the HypNP-DCD-1L-mediated aSDT (P<0.05). In addition, the quantitative real-time PCR data illustrated the high level of similarities in very low-expression profiles of the gtfD before and after all treated groups for persister cells. While, following HypNP-DCD-1L-mediated aSDT treatment, the expression levels of gtfD, comDE, and smuT were significantly lower in treated persister cells growing- and biofilm cultures of S. mutans in comparison with control groups (P<0.05).

CONCLUSIONS

Combined, the results of this study indicate that ultrasound waves-activated HypNP-DCD-1 L can sonoinactivate S. mutans biofilms and persister cells, as well as reduce effectively pathogenicity potency of S. mutans. Hence, HypNP-DCD-1L-mediated aSDT may be proposed as a promising adjunctive therapeutic approach for dental caries.

Recent Clinical and Preclinical Advances in External Stimuli-Responsive Therapies for Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) has long been one of the most prevalent cancers worldwide; even though treatments such as surgery, chemotherapy, radiotherapy and immunotherapy have been proven to benefit the patients and prolong their survival time, the overall five-year survival rate is still below 50%. Hence, the development of new therapies for better patient management is an urgent need. External stimuli-responsive therapies are emerging therapies with promising antitumor effects; therapies such as photodynamic (PDT) and photothermal therapies (PTT) have been tested clinically in late-stage HNSCC patients and have achieved promising outcomes, while the clinical translation of sonodynamic therapy (SDT), radiodynamic therapy (RDT), microwave dynamic/thermodynamic therapy, and magnetothermal/magnetodynamic therapy (MDT/MTT) still lag behind. In terms of preclinical studies, PDT and PTT are also the most extensively studied therapies. The designing of nanoparticles and combinatorial therapies of PDT and PTT can be referenced in designing other stimuli-responsive therapies in order to achieve better antitumor effects as well as less toxicity. In this review, we consolidate the advancements and limitations of various external stimuli-responsive therapies, as well as critically discuss the prospects of this type of therapies in HNSCC treatments.

An ex vivo evaluation of physico-mechanical and anti-biofilm properties of resin-modified glass ionomer containing ultrasound waves-activated nanoparticles against Streptococcus mutans biofilm around orthodontic bands

BACKGROUND

The present study evaluated the physico-mechanical and antimicrobial properties of ultrasound waves-activated modified-resin glass ionomer containing nanosonosensitizers such as nano-curcumin (n-Cur), nano-emodin (n-Emo), and nano-quercetin (n-Qct) against Streptococcus mutans biofilm on the surface of modified-resin glass ionomer bonded orthodontic bands.

MATERIALS AND METHODS

A total of 50 human molar teeth were used in this study. The shear bond strength (SBS), adhesive remnant index (ARI), setting time, and fluoride release of modified orthodontics cement containing different concentrations of n-Cur, n-Emo, and n-Qct (0, 2, 5, and 10%) were measured. The antimicrobial effectiveness was assessed against S. mutans by the biofilm inhibition test, and the Log₁₀ colony-forming unit (CFU)/mL was evaluated.

RESULTS

SBS and setting time of modified glass ionomer decreased compared with the control group. 5% n-Emo, 2% n-Qct, and 5% n-Cur were the highest concentrations that had an insignificant difference in comparison with Transbond XT (P = 0.647, 0.819, and 0.292, respectively). The groups were not significantly different in terms of ARI score (P > 0.05). The highest and lowest setting time belonged to the control and 5% n-Emo groups, respectively; this difference in setting time was significant (P < 0.05). Ultrasound waves and 0.2% CHX significantly reduced S. mutans biofilms compared with the control group (P < 0.001), and minimum S. mutans colony count was shown in 0.2% CHX and 5% n-Emo groups. The addition of nanosonosensitizers to the glass ionomer did not compromise the fluoride release of the glass ionomer.

CONCLUSION

It could be concluded that resin-modified glass ionomer containing ultrasound waves-activated 5% n-Emo reduces S. mutans biofilm around orthodontic bands with no adverse effect on SBS, ARI, and its application in the clinic.

Emodin Combined with Multiple-Low-Frequency, Low-Intensity Ultrasound To Relieve Osteomyelitis through Sonoantimicrobial Chemotherapy

Treatment of osteomyelitis is still challenging, as conventional antibiotic therapy is limited by the emergence of resistant strains and the formation of biofilms. Sonoantimicrobial chemotherapy (SACT) is a novel therapy of low-frequency and low-intensity ultrasound (LFLIU) combined with a sonosensitizer. Therefore, in our study, a sonosensitizer named emodin (EM) was proposed to be combined with LFLIU to relieve acute osteomyelitis caused by methicillin-resistant Staphylococcus aureus (MRSA) through antibacterial and antibiofilm effects. The efficiencies of different intensities of ultrasound, including single (S-LFLIU, 15 min) and multiple ultrasound (M-LFLIU, 3 times for 5 min at 4-h intervals), against bacteria and biofilms were compared, contributing to developing the best treatment regimen. Our results demonstrated that EM plus S-LFLIU or M-LFLIU (EM+S-LFLIU or EM+M-LFLIU) had significant combined bactericidal and antibiofilm effects, with EM+M-LFLIU in particular exhibiting superior antibiofilm performance. Furthermore, it was suggested that EM+M-LFLIU could produce a large amount of reactive oxygen species (ROS), destroy the integrity of the bacterial membrane and cell wall, and downregulate the expression of genes involved in oxidative stress, membrane wall synthesis, and bacterial virulence, as well as that of other related genes (agrB, pbp3, sgtB, gmk, zwf, and msrA). In vivo studies, micro-computed tomography (micro-CT), hematoxylin and eosin (H&E) staining, enzyme-linked immunosorbent assay (ELISA), and bacterial quantification of bone tissue indicated that EM+M-LFLIU could also relieve osteomyelitis due to MRSA infection. Our work proffers an original approach to bacterial osteomyelitis treatment that weakens drug-resistant bacteria and suppresses and degrades biofilm formation through SACT, which may provide new prospects for clinical treatment. IMPORTANCE Antibiotic therapy is the first choice for clinical treatment of osteomyelitis, but the formation of bacterial biofilms and the emergence of many drug-resistant strains also create an urgent need to find an alternative treatment to effectively eliminate the infection. Recently, LFLIU has come to be considered a safe and promising method of debridement and antibacterial therapy. In this study, we found that ultrasound and EM have a significant combined antibacterial effect in vivo and in vitro, which may play an antibacterial role by stimulating the production of ROS, destroying the bacterial cell wall, and inhibiting the expression of related genes. Our study expands the body of knowledge on the antibacterial effect of drugs-specifically emodin (EM)-through combined physiotherapy. If successfully integrated into clinical practice, these methods may reduce the burden of high concentrations of drugs needed to treat bacterial biofilms and avoid the growing resistance of bacteria to antibiotics.

Antitumor effects of Chinese herbal medicine compounds and their nano-formulations on regulating the immune system microenvironment

Traditional Chinese medicine (TCM), including herbal medicine, acupuncture and meditation, has a wide range of applications in China. In recent years, herbal compounding and active ingredients have been used to control tumor growth, reduce suffering, improve quality of life, and prolong the life span of cancer patients. To reduce side effects, herbal medicine can be used in conjunction with radiotherapy and chemotherapy or can be used as an adjuvant to strengthen the immune effect of anticancer vaccines. In particular, in the immunosuppressed tumor microenvironment, herbal medicine can have antitumor effects by stimulating the immune response. This paper reviews the advances in research on antitumor immunomodulation in Chinese herbal medicine, including the regulation of the innate immune system, which includes macrophages, MDSCs, and natural killer cells, and the adaptive immune system, which includes CD4+ T cells, CD8+ T cells, and regulatory T cells (Tregs), to influence tumor-associated inflammation. In addition, a combination of active ingredients of herbal medicine and modern nanotechnology alter the tumor immune microenvironment. In recent years, immunological antitumor therapy in TCM has been applied on a reasonably large scale both nationally and internationally, and there is potential for further clinical expansion. Investigation of immune modulation mechanisms in Chinese herbal medicine will provide novel perspectives of how herbal medicine controls tumor growth and metastasis, which will contribute to the evolution of tumor research.

Aptamer decorated emodin nanoparticles-assisted delivery of dermcidin-derived peptide DCD-1L: Photoactive bio-theragnostic agent for Enterococcus faecalis biofilm destruction

BACKGROUND

Despite the high success rate of root canal treatment, failures are observed in a broad range of cases. Therefore, the need for novel approaches with the development of new generations of antimicrobial agents and intracellular drug delivery systems as adjunctive therapy is undeniable. In this study, we investigated the antimicrobial effects of antimicrobial photodynamic therapy (aPDT) using dermcidin‑derived peptide DCD‑1L loaded onto aptamer-functionalized emodin nanoparticles (Apt@EmoNp-DCD-1L) against Enterococcus faecalis as one of the most common bacteria involved in recurrent root canal treatment failures.

MATERIALS AND METHODS

Following preparation of EmoNp-DCD-1L, the binding of selected labeled Apt to EmoNp-DCD-1L was performed, followed by the specificity of Apt@EmoNp-DCD-1L to E. faecalis was determined. The antimicrobial potential of aPDT was then assessed after the determination of the minimum inhibitory concentration (MIC) of Apt@EmoNp-DCD-1L. The molecular docking analysis was conducted to evaluate the potential binding modes of EmoNp to the proteins involved in E. faecalis pathogenesis. Eventually, the anti-virulence capacity of Apt@EmoNp-DCD-1L-mediated aPDT was investigated via quantitative real-time PCR (qRT-PCR) assay following measurement of intracellular reactive oxygen species (ROS) generation.

RESULTS

The binding specificity of Apt@EmoNp-DCD-1L to E. faecalis was confirmed by flow cytometry. The results showed that the cell viability of E. faecalis exposed to aPDT groups employing the sub-MIC doses of Apt@EmoNp-DCD-1L (7.8 and 15.6 µM) was significantly reduced compared to the control group (P < 0.05). Also, Apt@EmoNp-DCD-1L in combination with a blue laser light was capable of enhancing the anti-biofilm activity of aPDT against E. faecalis biofilm. Data obtained from the qRT-PCR analysis showed significant downregulation in the expression level of genes involved in bacterial biofilm formation after exposure to aPDT (P < 0.05).

CONCLUSIONS

This in vitro study highlights that aPDT with the minimum concentration of Apt@EmoNp-DCD-1L can be considered as a targeted bio-theragnostic agent for the detection and elimination of E. faecalis in the dispersed and biofilm states.

Theranostic nanoplatforms of emodin-chitosan with blue laser light on enhancing the anti-biofilm activity of photodynamic therapy against Streptococcus mutans biofilms on the enamel surface

Background

Combining photosensitizer and light irradiation, named antimicrobial photodynamic therapy (aPDT) is an adjuvant therapy for eliminating microbial biofilms. This ex vivo study evaluates the effect of anti-biofilm activity of aPDT based on emodin-chitosan nanoparticles (Emo-CS-NPs) plus blue laser light against Streptococcus mutans biofilm on the enamel surface.

Materials

After determination of the fractional inhibitory concentration index of Emo and CS by checkerboard array assay, Emo-CS-NPs were synthesized and characterized. Following treatment of pre-formed S. mutans biofilms on the enamel slabs, cellular uptake of Emo-CS-NPs and intracellular reactive oxygen species (ROS) production were determined. The anti-biofilm and anti-metabolic activities of aPDT were investigated. Eventually, lactic acid production capacity, concentrations of S. mutans extracellular DNA (eDNA) levels, and expression of the gene involved in the biofilm formation (gtfB) were evaluated.

Results

The maximum uptake of Emo-CS-NPs occurs in an incubation time of 5 min. When irradiated, Emo-CS-NPs were photoactivated, generating ROS, and led to a decrease in the cell viability and metabolic activity of S. mutans significantly (P < 0.05). S. mutans eDNA and lactic acid production outcomes indicated that Emo-CS-NPs-mediated aPDT led to a significant reduction of eDNA levels (48%) and lactic acid production (72.4%) compared to the control group (P < 0.05). In addition, gtfB mRNA expression in S. mutans was downregulated (7.8-fold) after aPDT in comparison with the control group (P < 0.05).

Conclusions

Our data support that, aPDT using Emo-CS-NPs revealed the highest cellular uptake and ROS generation. Emo-CS-NPs based aPDT could inhibit significantly biofilm formation and reduce effectively virulence potency of S. mutans; thus, it could be an adjuvant therapy against dental caries.

Is Emodin with Anticancer Effects Completely Innocent? Two Sides of the Coin

Many anticancer active compounds are known to have the capacity to destroy pathologically proliferating cancer cells in the body, as well as to destroy rapidly proliferating normal cells. Despite remarkable advances in cancer research over the past few decades, the inclusion of natural compounds in researches as potential drug candidates is becoming increasingly important. However, the perception that the natural is reliable is an issue that needs to be clarified. Among the various chemical classes of natural products, anthraquinones have many biological activities and have also been proven to exhibit a unique anticancer activity. Emodin, an anthraquinone derivative, is a natural compound found in the roots and rhizomes of many plants. The anticancer property of emodin, a broad-spectrum inhibitory agent of cancer cells, has been detailed in many biological pathways. In cancer cells, these molecular mechanisms consist of suppressing cell growth and proliferation through the attenuation of oncogenic growth signaling, such as protein kinase B (AKT), mitogen-activated protein kinase (MAPK), HER-2 tyrosine kinase, Wnt/-catenin, and phosphatidylinositol 3-kinase (PI3K). However, it is known that emodin, which shows toxicity to cancer cells, may cause kidney toxicity, hepatotoxicity, and reproductive toxicity especially at high doses and long-term use. At the same time, studies of emodin, which has poor oral bioavailability, to transform this disadvantage into an advantage with nano-carrier systems reveal that natural compounds are not always directly usable compounds. Consequently, this review aimed to shed light on the anti-proliferative and anti-carcinogenic properties of emodin, as well as its potential toxicities and the advantages of drug delivery systems on bioavailability.