Betel Nut Arecoline Induces Different Phases of Growth Arrest between Normal and Cancerous Prostate Cells through the Reactive Oxygen Species Pathway

Bioactive Components of Areca Nut: An Overview of Their Positive Impacts Targeting Different Organs

Areca catechu L. is a widely cultivated tropical crop in Southeast Asia, and its fruit, areca nut, has been consumed as a traditional Chinese medicinal material for more than 10,000 years, although it has recently attracted widespread attention due to potential hazards. Areca nut holds a significant position in traditional medicine in many areas and ranks first among the four southern medicines in China. Numerous bioactive compounds have been identified in areca nuts, including alkaloids, polyphenols, polysaccharides, and fatty acids, which exhibit diverse bioactive functions, such as anti-bacterial, deworming, anti-viral, anti-oxidant, anti-inflammatory, and anti-tumor effects. Furthermore, they also display beneficial impacts targeting the nervous, digestive, and endocrine systems. This review summarizes the pharmacological functions and underlying mechanisms of the bioactive ingredients in areca nut. This helps to ascertain the beneficial components of areca nut, discover its medicinal potential, and guide the utilization of the areca nut.

Epigallocatechin-3-gallate Synergistically Enhanced Arecoline-Induced Cytotoxicity by Redirecting Cycle Arrest to Apoptosis

Carcinogens, such as arecoline, play a crucial role in cancer progression and continuous gene mutations by generating reactive oxygen species (ROS). Antioxidants can reduce ROS levels and potentially prevent cancer progression but may paradoxically enhance the survival of cancer cells. This study investigated whether epigallocatechin-3-gallate (EGCG), an antioxidant from green tea, could resolve this paradox. Prostate cancer cells (PC-3 cell line) were cultured and treated with arecoline combined with NAC (N-acetylcysteine) or EGCG; the combined effects on intracellular ROS levels and cell viability were examined using the MTT and DCFDA assays, respectively. In addition, apoptosis, cell cycle, and protein expression were investigated using flow cytometry and western blot analysis. Our results showed that EGCG, similar to NAC (N-acetylcysteine), reduced the intracellular ROS levels, which were elevated by arecoline. Moreover, EGCG not only caused cell cycle arrest but also facilitated cell apoptosis in arecoline-treated cells in a synergistic manner. These were evidenced by elevated levels of cyclin B1 and p27, and increased fragmentation of procaspase-3, PARP, and DNA. Our findings highlight the potential use of EGCG for cancer prevention and therapy.

Arecoline hydrobromide suppresses PI3K/AKT pathway in rheumatoid arthritis synovial fibroblasts and relieves collagen-induced arthritis in mice

OBJECTIVE

This study investigated the effectiveness of arecoline hydrobromide (AH) on the functions of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLSs) and collagen-induced arthritis (CIA) mice.

METHODS

Immunofluorescence was used to identify RA-FLSs. Cell Counting Kit-8 (CCK-8) was used to determine the viability of RA-FLSs and the half maximal inhibitory concentration (IC50) of AH. The 5-ethynyl-2'-deoxyuridine (EdU) assay was used to detect DNA replication in RA-FLSs. Cell cycle and apoptosis were examined by flow cytometry. Migration and invasion, as well as wound healing assays, were employed to determine cell migration and invasion ability. Proteins and mRNA expression levels were investigated using Western blot, quantitative real-time PCR (RT-qPCR), and immunofluorescence. The CIA mice model was used to assess the effect of AH in vivo. RNA-sequencing (RNA-seq) was used to find the potential signaling pathways of AH against RA, and Western blot was used to verify the key signaling pathway of AH on RA-FLSs. Network pharmacology and molecular docking were used to predict drug targets.

RESULTS

AH inhibited the proliferation and DNA replication of RA-FLSs, promoted cell cycle arrest by reducing the levels of cyclin-dependent kinase 1 (CDK1), cyclin A2, and cyclin B1, promoted apoptosis by suppressing B-cell lymphoma-2 (Bcl-2) expression, and suppressed migration and invasion by inhibiting vimentin expression in RA-FLSs. AH was also effective in relieving arthritis in vivo. RNA sequencing analyses suggested that AH inhibited the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway in RA-FLSs, which was also confirmed in Western blot analysis. Furthermore, network pharmacology and molecular docking suggested that F2, MAPK14, SRC, AKT1, and CTSK might be the direct targets of AH.

CONCLUSION

AH can modulate the pathological process of RA-FLSs by blocking the PI3K/AKT pathway and relieve CIA in mice, making it a potential new small molecule candidate.

Senescent epithelial cells remodel the microenvironment for the progression of oral submucous fibrosis through secreting TGF-β1

Objectives

Cellular senescence is strongly associated with fibrosis and tumorigenesis. However, whether the epithelium of oral submucous fibrosis (OSF) undergoes premature senescence remains unclear. This study investigates the roles of senescent epithelial cells in OSF.

Methods

The immunohistochemistry and Sudan black B staining were performed to identify epithelium senescence in OSF tissues. Arecoline was used to induce human oral keratinocytes (HOKs) senescence. The cell morphology, senescence-associated β galactosidase activity, cell counting Kit 8, immunofluorescence, quantitative real-time PCR, and western blot assay were used to identification of senescent HOKs. The enzyme-linked immunosorbent assay was exerted to evaluate the levels of transforming growth factor β1 (TGF-β1) in the supernatants of HOKs treated with or without arecoline.

Results

The senescence-associated markers, p16 and p21, were overexpressed in OSF epithelium. These expressions were correlated with alpha-smooth actin (α-SMA) positively and proliferating cell nuclear antigen (PCNA) negatively. Moreover, Sudan black staining showed that there was more lipofuscin in OSF epithelium. In vitro, HOKs treated with arecoline showed senescence-associated characteristics including enlarged and flattened morphology, senescence-associated β galactosidase staining, cell growth arrest, γH2A.X foci, upregulation of p53, p21, and TGF-β1 protein levels. Moreover, senescent HOKs secreted more TGF-β1.

Conclusions

Senescent epithelial cells are involved in OSF progression and may become a promising target for OSF treatment.

Oral Cancer Disparities in the Outer US-affiliated Pacific Islands

OBJECTIVE/HYPOTHESIS

Oral cancers in the US-affiliated Pacific Islands are poorly described despite disproportionately higher incidences in certain jurisdictions. This study attempts to better characterize the incidence, staging, and management of oral cancers in this region.

STUDY DESIGN

Retrospective Epidemiological Study.

METHODS

A retrospective review was conducted across the US-affiliated Pacific Islands between 2007 and 2019. Patient data were obtained for individuals with primary head and neck cancers from the Pacific Regional Central Cancer Registry database. All cohorts were age-adjusted to the 2000 US Standard Population. Further analysis was performed on oral cavity cancers due to their clear predominance within the sample.

RESULTS

A total of 585 patients with primary head and neck cancers were included. The average age was 54.5 ± 12.9 years, and most patients were male (76.8%). Oral cancer subsite analysis revealed the proportional incidence of buccal mucosa was higher in 5 of 9 jurisdictions when compared with the United States (p < 0.001). Tongue and lip cancers were not found to have significantly higher incidence proportions. Patients in the Pacific Islander group were less likely to be detected at earlier stages for cancers of the cheek and other mouth (p < 0.001), tongue (p < 0.001), and lips (p < 0.001) compared with the United States.

CONCLUSIONS

Many Pacific Island populations are burdened with higher incidences of oral cancer with later staging. Further investigation is recommended to evaluate oral cancer-related outcomes and mortality in this region.

LEVEL OF EVIDENCE

3 Laryngoscope, 2022.

N-acetyl cysteine prevents arecoline-inhibited C2C12 myoblast differentiation through ERK1/2 phosphorylation

Arecoline is known to induce reactive oxygen species (ROS). Our previous studies showed that arecoline inhibited myogenic differentiation and acetylcholine receptor cluster formation of C2C12 myoblasts. N-acetyl-cysteine (NAC) is a known ROS scavenger. We hypothesize that NAC scavenges the excess ROS caused by arecoline. In this article we examined the effect of NAC on the inhibited myoblast differentiation by arecoline and related mechanisms. We found that NAC less than 2 mM is non-cytotoxic to C2C12 by viability analysis. We further demonstrated that NAC attenuated the decreased number of myotubes and nuclei in each myotube compared to arecoline treatment by H & E staining. We also showed that NAC prevented the decreased expression level of the myogenic markers, myogenin and MYH caused by arecoline, using immunocytochemistry and western blotting. Finally, we found that NAC restored the decreased expression level of p-ERK1/2 by arecoline. In conclusion, our results indicate that NAC attenuates the damage of the arecoline-inhibited C2C12 myoblast differentiation by the activation/phosphorylation of ERK. This is the first report to demonstrate that NAC has beneficial effects on skeletal muscle myogenesis through ERK1/2 upon arecoline treatment. Since defects of skeletal muscle associates with several diseases, NAC can be a potent drug candidate in diseases related to defects in skeletal muscle myogenesis.

Sirtuins and Sepsis: Cross Talk between Redox and Epigenetic Pathways

Sepsis and septic shock are the leading causes of death among hospitalized patients in the US. The immune response in sepsis transitions from a pro-inflammatory and pro-oxidant hyper-inflammation to an anti-inflammatory and cytoprotective hypo-inflammatory phase. While 1/3rd sepsis-related deaths occur during hyper-, a vast majority of sepsis-mortality occurs during the hypo-inflammation. Hyper-inflammation is cytotoxic for the immune cells and cannot be sustained. As a compensatory mechanism, the immune cells transition from cytotoxic hyper-inflammation to a cytoprotective hypo-inflammation with anti-inflammatory/immunosuppressive phase. However, the hypo-inflammation is associated with an inability to clear invading pathogens, leaving the host susceptible to secondary infections. Thus, the maladaptive immune response leads to a marked departure from homeostasis during sepsis-phases. The transition from hyper- to hypo-inflammation occurs via epigenetic programming. Sirtuins, a highly conserved family of histone deacetylators and guardians of homeostasis, are integral to the epigenetic programming in sepsis. Through their anti-inflammatory and anti-oxidant properties, the sirtuins modulate the immune response in sepsis. We review the role of sirtuins in orchestrating the interplay between the oxidative stress and epigenetic programming during sepsis.

MEX3A knockdown inhibits the tumorigenesis of colorectal cancer via modulating CDK2 expression

Colorectal cancer (CRC) is a malignant tumor of the gastrointestinal tract and a leading cause of cancer-associated mortality worldwide. Mex-3 RNA binding family member A (MEX3A) promotes the progression of multiple types of cancer, including ovarian and cervical cancer. However, to the best of our knowledge, the role of MEX3A in CRC is not completely understood. Therefore, the present study aimed to investigate the function of MEX3A in CRC. The mRNA and protein expression levels of MEX3A in CRC cells were analyzed using reverse transcription-quantitative PCR and western blotting, respectively. Cell Counting Kit-8 assays were used to measure cell viability. Cell apoptosis and cell cycle distribution were detected via flow cytometry, and CRC cell invasion was analyzed by performing Transwell assays. Moreover, the mitochondrial membrane potential in CRC cells was measured via JC-1 staining. The results of the present study revealed that the expression levels of MEX3A were upregulated in CRC tissues compared with adjacent healthy tissues. MEX3A knockdown notably inhibited CRC cell viability, and induced apoptosis and mitochondrial injury. In addition, MEX3A knockdown markedly induced G₁ phase cell cycle arrest in CRC cells via downregulating CDK2 expression. In conclusion, the findings of the present study suggested that MEX3A knockdown may inhibit the tumorigenesis of CRC cells by regulating CDK2 expression. Therefore, MEX3A may serve as a novel target for CRC treatment.

Therapeutic Applications of Functional Nanomaterials for Prostatitis

Prostatitis is a common disease in adult males, with characteristics of a poor treatment response and easy recurrence, which seriously affects the patient's quality of life. The prostate is located deep in the pelvic cavity, and thus a traditional infusion or other treatment methods are unable to easily act directly on the prostate, leading to poor therapeutic effects. Therefore, the development of new diagnostic and treatment strategies has become a research hotspot in the field of prostatitis treatment. In recent years, nanomaterials have been widely used in the diagnosis and treatment of various infectious diseases. Nanotechnology is a promising tool for 1) the accurate diagnosis of diseases; 2) improving the targeting of drug delivery systems; 3) intelligent, controlled drug release; and 4) multimode collaborative treatment, which is expected to be applied in the diagnosis and treatment of prostatitis. Nanotechnology is attracting attention in the diagnosis, prevention and treatment of prostatitis. However, as a new research area, systematic reviews on the application of nanomaterials in the diagnosis and treatment of prostatitis are still lacking. In this mini-review, we will highlight the treatment approaches for and challenges associated with prostatitis and describe the advantages of functional nanoparticles in improving treatment effectiveness and overcoming side effects.

Therapeutic Applications of Functional Nanomaterials for Prostatitis

Prostatitis is a common disease in adult males, with characteristics of a poor treatment response and easy recurrence, which seriously affects the patient’s quality of life. The prostate is located deep in the pelvic cavity, and thus a traditional infusion or other treatment methods are unable to easily act directly on the prostate, leading to poor therapeutic effects. Therefore, the development of new diagnostic and treatment strategies has become a research hotspot in the field of prostatitis treatment. In recent years, nanomaterials have been widely used in the diagnosis and treatment of various infectious diseases. Nanotechnology is a promising tool for 1) the accurate diagnosis of diseases; 2) improving the targeting of drug delivery systems; 3) intelligent, controlled drug release; and 4) multimode collaborative treatment, which is expected to be applied in the diagnosis and treatment of prostatitis. Nanotechnology is attracting attention in the diagnosis, prevention and treatment of prostatitis. However, as a new research area, systematic reviews on the application of nanomaterials in the diagnosis and treatment of prostatitis are still lacking. In this mini-review, we will highlight the treatment approaches for and challenges associated with prostatitis and describe the advantages of functional nanoparticles in improving treatment effectiveness and overcoming side effects.