Perillaldehyde: A promising antifungal agent to treat oropharyngeal candidiasis

Antimicrobial peptide AMP-17 induces protection against systemic candidiasis and interacts synergistically with fluconazole against Candida albicans biofilm

Candida albicans, a common commensal and opportunistic fungal pathogen in humans, can occasionally progress to disseminated candidiasis which is a serious condition with a high morbidity and fatality rate. The emergence of drug-resistant fungal strains compels us to look for an efficient treatment solution. Our earlier studies have demonstrated that the unique antimicrobial peptide AMP-17 from Musca domestica has a strong antifungal impact on C. albicans in vitro. Here, we verified the therapeutic effects of AMP-17 on systemic candidiasis in vivo and the peptide interacts with fluconazole, a common antifungal medication, to treat systemic candidiasis. In the disseminated candidiasis model of Galleria mellonella and mice challenged with C. albicans, AMP-17 increased the survival rates of infected larvae and mice to 66.7 and 75%, respectively. Furthermore, the peptide lowered the load of C. albicans in the infected larvae and the kidneys of the mice by nearly 90%. Additional histological examination and measurements of plasma cytokines showed that the injection of AMP-17 markedly reduced the inflammatory response and balanced cytokine expression. Furthermore, checkerboard micro dilution experiments demonstrated that AMP-17 and fluconazole worked in synergy to inhibit C. albicans in the biofilm mode. According to morphological studies, AMP-17 and fluconazole together decreased the production of hyphae throughout the C. albicans biofilm formation process, loosening the mature biofilms' structure and lowering the amount of carbohydrates in the extracellular matrix (ECM) of the biofilms. Taken together, these results showed that AMP-17 would be a viable treatment for systemic candidiasis and might be a different approach to combating Candida biofilm, either by itself or in conjunction with fluconazole.

Integration of Gut Mycobiota and Oxidative Stress to Decipher the Roles of C-Type Lectin Receptors in Inflammatory Bowel Diseases

BACKGROUND

Ulcerative colitis (UC) and Crohn's disease (CD) are two subtypes of inflammatory bowel disease (IBD) with rapidly increased incidence worldwide. Although multiple factors contribute to the occurrence and progression of IBD, the role of intestinal fungal species (gut mycobiota) in regulating the severity of these conditions has been increasingly recognized. C-type lectin receptors (CLRs) on hematopoietic cells, including Dectin-1, Dectin-2, Dectin-3, Mincle and DC-SIGN, are a group of pattern recognition receptors (PRRs) that primarily recognize fungi and mediate defense responses, such as oxidative stress. Recent studies have demonstrated the indispensable role of CLRs in protecting the colon from intestinal inflammation and mucosal damage.

METHODS AND RESULTS

This review provides a comprehensive overview of the role of CLRs in the pathogenesis of IBD. Given the significant impact of mycobiota and oxidative stress in IBD, this review also discusses recent advancements in understanding how these factors exacerbate or ameliorate IBD. Furthermore, the latest developments in CLR-guided IBD therapy are examined to highlight the modulation of CLRs in fungal recognition and oxidative burst during the IBD process.

CONCLUSION

This review emphasizes the importance of CLRs in IBD, offering new perspectives on the etiology and therapeutic approaches for this disease.

The Antiviral Potential of Perilla frutescens: Advances and Perspectives

Viruses pose a significant threat to human health, causing widespread diseases and impacting the global economy. Perilla frutescens, a traditional medicine and food homologous plant, is well known for its antiviral properties. This systematic review examines the antiviral potential of Perilla frutescens, including its antiviral activity, chemical structure and pharmacological parameters. Utilizing bioinformatics analysis, we revealed the correlation between Perilla frutescens and antiviral activity, identified overlaps between Perilla frutescens target genes and virus-related genes, and explored related signaling pathways. Moreover, a classified summary of the active components of Perilla frutescens, focusing on compounds associated with antiviral activity, provides important clues for optimizing the antiviral drug development of Perilla frutescens. Our findings indicate that Perilla frutescens showed a strong antiviral effect, and its active ingredients can effectively inhibit the replication and spread of a variety of viruses in this review. The antiviral mechanisms of Perilla frutescens may involve several pathways, including enhanced immune function, modulation of inflammatory responses, and inhibition of key enzyme activities such as viral replicase. These results underscore the potential antiviral application of Perilla frutescens as a natural plant and provide important implications for the development of new antiviral drugs.

Holotoxin A1 from Apostichopus japonicus inhibited oropharyngeal and intra-abdominal candidiasis by inducing oxidative damage in Candida albicans

BACKGROUND AND PURPOSE

The holotoxin A1, isolated from Apostichopus japonicus, exhibits potent antifungal activities, but the mechanism and efficacy against candidiasis are unclear. In this study we have studied the antifungal effects and mechanism of holotoxin A1 against Candida albicans and in murine oropharyngeal and intra-abdominal candidiasis.

EXPERIMENTAL APPROACH

The antifungal effect of holotoxin A1 against C. albicans was tested in vitro. To explore the antifungal mechanism of holotoxin A1, the transcriptome, ROS levels, and mitochondrial function of C. albicans was evaluated. Effectiveness and systematic toxicity of holotoxin A1 in vivo was assessed in the oropharyngeal and intra-abdominal candidiasis models in mice.

KEY RESULTS

Holotoxin A1 was a potent fungicide against C. albicans SC5314, clinical strains and drug-resistant strains. Holotoxin A1 inhibited oxidative phosphorylation and induced oxidative damage by increasing intracellular accumulation of ROS in C. albicans. Holotoxin A1 induced dysfunction of mitochondria by depolarizing the mitochondrial membrane potential and reducing the production of ATP. Holotoxin A1 directly inhibited the enzymatic activity of mitochondrial complex I and antagonized with the rotenone, an inhibitor of complex I, against C. albicans. Meanwhile, the complex I subunit NDH51 null mutants showed a decreased susceptibility to holotoxin A1. Furthermore, holotoxin A1 significantly reduced fungal burden and infections with no significant systemic toxicity in oropharyngeal and intra-abdominal candidiasis in murine models.

CONCLUSION AND IMPLICATIONS

Holotoxin A1 is a promising candidate for the development of novel antifungal agents against both oropharyngeal and intra-abdominal candidiasis, especially when caused by drug-resistant strains.

Role of mitochondrial farnesyltransferase gene in the prevention of the food spoilage fungi Aspergillus flavus by the antimicrobial natural preservative perillaldehyde

Aspergillus flavus, one of the most widely distributed and abundant genus of Aspergillus worldwide, poses an evident threat as a source of food contamination in grains and cereals. Perillaldehyde (PAE), a volatile essential oil extracted from the stem and leaves of Perilla frutescens L., exhibits potent antifungal activity. In our study, we investigated the role of Cox10, a key enzyme in the heme A synthesis pathway crucial for maintaining mitochondrial function. We found that cox10 is a sensitive gene of A. flavus in response to PAE by gene expression assay and GFP fluorescent localization tagging, and then we found that the deletion of this gene affects the growth and development of A. flavus, but the drug resistance is elevated. Through transcriptome sequencing and its experimental validation, the molecular mechanisms of stress triggered by the deletion of cox10 were further clarified, such as the decrease in intracellular drug content due to the increase in the expression of drug efflux proteins, and the increase in the thickness of cell wall due to the increase in the content of cell wall chitin. Clearly, cox10 plays a critical role in regulating various cellular processes of A. flavus, including growth, reproduction, development, as well as pathogenicity and drug resistance. These significant findings establish a solid theoretical foundation for the development of environmentally friendly, safe, and effective antifungal agents to combat A. flavus contamination.

Perillaldehyde: A promising antibacterial agent for the treatment of pneumonia caused by Acinetobacter baumannii infection

Perillaldehyde is a monoterpene compound mainly from the medicinal plant Perilla frutescens (L.) Britt., which has hypolipidemic, antioxidant, antibacterial and anti-inflammatory functions. In this investigation, we discovered that Perillaldehyde had powerful antimicrobial activity against Acinetobacter baumannii 5F1, and its minimum inhibitory concentration was 287.08 μg/mL. A. baumannii is a conditionally pathogenic bacterium with a high clinical resistance rate and is a major source of hospital infections, especially in intensive care units, which is one of the main causes of pneumonia. Inflammatory immune response is characteristic of pneumonia caused by A. baumannii infection. The results of our in vitro experiments indicate that Perillaldehyde disrupts the cell membrane of A. baumannii 5F1 and inhibits its quorum sensing to inhibit biofilm formation, among other effects. With an experimental model of murine pneumonia, we investigated that Perillaldehyde decreased NLRP3 inflammasome activation and TNF-α expression in lung tissues by inhibiting the NF-κB pathway, and also impacted MAPKs protein signaling pathway through the activation of TLR4. Notably, the use of high doses of Perillaldehyde for the treatment of pneumonia caused by A. baumannii 5F1 infection resulted in a survival rate of up to 80 % in mice. In summary, we demonstrated that Perillaldehyde is promising as a new drug for the treatment of pneumonia caused by A. baumannii 5F1 infection.

Comparative Metabolomics Analysis of Different Perilla Varieties Provides Insights into Variation in Seed Metabolite Profiles and Antioxidant Activities

Perilla seeds are essential functional foods and key ingredients in traditional medicine. Herein, we investigated the variation in phytochemical profiles and antioxidant activities of twelve different perilla seeds. The seeds showed significant variations in total phenolic and flavonoid contents ranging from 16.92 to 37.23 mg GAE/g (GAE, gallic acid equivalent) and 11.6 to 19.52 mg CAE/g (CAE, catechin equivalent), respectively. LC-QqQ-MS (liquid chromatography triple quadrupole tandem mass spectrometry)-based widely targeted metabolic profiling identified a total of 975 metabolites, including 68-269 differentially accumulated metabolites (DAMs). Multivariate analyses categorized the seeds into four groups based on the seed coat and leaf colors. Most key bioactive DAMs, including flavonoids (quercetin-3'-O-glucoside, prunin, naringenin, naringenin chalcone, butin, genistin, kaempferol-3-O-rutinoside, etc.), amino acids (valine, lysine, histidine, glutamine, threonine, etc.), and vitamins (B1, B3, B6, U, etc.) exhibited the highest relative content in PL3 (brown seed, purple leaf), PL1 (white seed, green-purple leaf), and PL4 (white seed, green leaf) groups, respectively. Meanwhile, key differentially accumulated phenolic acids showed a higher relative content in PL1 and PL4 than in other groups. Both seeds exhibited high antioxidant activities, although those of PL2 (brown seed, green leaf) group seeds were the lowest. Our results may facilitate the comprehensive use of perilla seeds in food and pharmaceutical industries.

Perillaldehyde Mitigates Ionizing Radiation-Induced Intestinal Injury by Inhibiting Ferroptosis via the Nrf2 Signaling Pathway

SCOPE

Gastrointestinal toxicity is one of the major side effects of abdominopelvic tumor radiotherapy. Studies have shown that perillaldehyde (PAH) has antioxidant, antiinflammatory, antimicrobial activity, and antitumor effects. This study aims to determine whether PAH has radioprotective effects on radiation-induced intestinal injury and explore the underlying mechanisms.

METHODS AND RESULTS

C57BL/6J mice are gavaged with PAH for 7 days, then exposed to a single dose of 13 Gy X-ray total abdominal irradiation (TAI). PAH treatment prolongs the survival time, promotes the survival of crypt cells, attenuates radiation-induced DNA damage, and mitigates intestinal barrier damage in the irradiated mice. PAH also shows radioprotective effects in intestinal crypt organoids and human intestinal epithelial cells (HIEC-6). PAH-mediated radioprotection is associated with the upregulation of nuclear factor erythroid-2 related factor 2 (Nrf2), activation of the antioxidant pathway, and inhibition of ferroptosis. Notably, treatment with the Nrf2 inhibitor ML385 abolishes the protective effects of PAH, indicating that Nrf2 activation is essential for PAH activity.

CONCLUSION

PAH inhibits ionizing radiation (IR)-induced ferroptosis and attenuates intestinal injury after irradiation by activating Nrf2 signaling. Therefore, PAH is a promising therapeutic strategy for IR-induced intestinal injury.

Perspective on receptor-associated immune response to Candida albicans single and mixed infections: Implications for therapeutics in oropharyngeal candidiasis

Oropharyngeal candidiasis (OPC), commonly known as 'thrush', is an oral infection that usually dismantles oral mucosal integrity and malfunctions local innate and adaptive immunities in compromised individuals. The major pathogen responsible for the occurrence and progression of OPC is the dimorphic opportunistic commensal Candida albicans. However, the incidence induced by non-albicans Candida species including C. glabrata, C. tropicalis, C. dubliniensis, C. parapsilosis, and C. krusei are increasing in company with several oral bacteria, such as Streptococcus mutans, S. gordonii, S. epidermidis, and S. aureus. In this review, the microbiological and infection features of C. albicans and its co-contributors in the pathogenesis of OPC are outlined. Since the invasion and concomitant immune response lie firstly on the recognition of oral pathogens through diverse cellular surface receptors, we subsequently emphasize the roles of epidermal growth factor receptor, ephrin-type receptor 2, human epidermal growth factor receptor 2, and aryl hydrocarbon receptor located on oral epithelial cells to delineate the underlying mechanism by which host immune recognition to oral pathogens is mediated. Based on these observations, the therapeutic approaches to OPC comprising conventional and non-conventional antifungal agents, fungal vaccines, cytokine and antibody therapies, and antimicrobial peptide therapy are finally overviewed. In the face of newly emerging life-threatening microbes (C. auris and SARS-CoV-2), risks (biofilm formation and interconnected translocation among diverse organs), and complicated clinical settings (HIV and oropharyngeal cancer), the research on OPC is still a challenging task.

The effect of herbal medicine in innate immunity to Candida albicans

Candida albicans (C. albicans) is an opportunistic pathogenic fungus that often causes mucosal and systemic infections. Several pattern recognition receptors (PRRs), such as Toll-like receptors (TLRs) and C-type lectin receptors (CLRs), have been implicated in the host recognition of C. albicans. These PRRs recognize the pathogen-associated molecular patterns (PAMPs) of C. albicans to activate innate immune cells, thereby rapidly inducing various inflammatory responses by activating intracellular signaling cascades. Herbal medicine and its active components deserve priority development due to their low toxicity and high antibacterial, antiviral and antifungal activities. This review discussed the activities of herbal compounds against C. albicans and their related mechanisms, especially their regulatory role on innate immune cells such as neutrophils, macrophages, and dendritic cells (DCs) implicated in C. albicans infections. Our work aims to find new therapeutic drugs and targets to prevent and treat diseases caused by C. albicans infection with the mechanisms by which this fungus interacts with the innate immune response.

Perilla frutescens: A traditional medicine and food homologous plant

Perilla frutescens, an annual herb of the Labiatae family, has been cultivated in China for more than 2000 years. P. frutescens is the one of the first medicinal and edible plant published by the Ministry of Health. Its leaves, stems and seeds can be used as medicine and edible food. Because of the abundant nutrients and bioactive components in this plant, P. frutescens has been studied extensively in medicine, food, health care and chemical fields with great prospects for development. This paper reviews the cultivation history, chemical compositions and pharmacological activities of P. frutescens, which provides a reference for the development and utilization of P. frutescens resources.

Riboflavin Targets the Cellular Metabolic and Ribosomal Pathways of Candida albicans In Vitro and Exhibits Efficacy against Oropharyngeal Candidiasis

Oropharyngeal candidiasis (OPC), which has a high incidence in immunocompromised and denture stomatitis patients, is commonly caused by Candida albicans infection and in some cases develops into disseminated candidiasis throughout the throat and esophagus, resulting in high mortality. New drugs are needed to combat OPC because of the limited treatment options currently available and increasing resistance to existing drugs. Here, we confirmed that riboflavin (RF), a cofactor of flavin adenine mononucleotide and flavin adenine dinucleotide, has broad-spectrum anti-Candida activity. The formation of C. albicans hyphae and biofilm was inhibited by RF. Mechanistically, RF disrupted membrane and cell wall integrity, as well as promoting reactive oxygen species and pyruvate accumulation. Furthermore, RF targeted multiple essential pathways via functional disruption of thiamine and RF metabolic pathways, central carbon metabolism, and ribosome metabolism. Similar to the results in vitro, the inhibitory effect of RF on C. albicans hyphae was confirmed in a mouse model of OPC. Moreover, after 5 consecutive days of intraperitoneal injection, RF exhibited therapeutic efficacy, as demonstrated by phenotype investigation, the fungal burden, and histopathological analysis. These findings revealed that RF exerts a multifaceted anti-Candida effect and has potential benefits in the treatment of OPC. IMPORTANCE Candida species are common pathogens in fungal infections, causing mucosal infection and invasive infection in immunodeficient patients. Given the limited classes of drugs and resistance to these drugs, new antifungal agents need to be developed. Drug repurposing is a potential method for antifungal drug development. This study demonstrated that riboflavin (RF) exhibited broad-spectrum anti-Candida activity. RF affected multiple targets involving the membrane and cell wall integrity, the accumulation of reactive oxygen species and pyruvate, and the altered metabolic pathways in C. albicans. Moreover, RF exhibited efficacy in the treatment of C. albicans in an oropharyngeal candidiasis mouse model. Taken together, the antifungal activity and the promising clinical application of RF were highlighted.

Antifungal activity of vitamin D3 against Candida albicans in vitro and in vivo

The incidence of intra-abdominal candidiasis (IAC), characterized by high morbidity and mortality, has become a serious concern. The limitations of current antifungal drugs on the market underscores the importance of the development of novel antifungal agents. In the present study, the antifungal activity of vitamin D₃ (VD₃) against various Candida species was investigated. In vitro, the broth microdilution method and solid plate assay confirmed that VD₃ inhibited the growth of Candida spp. in a broad-spectrum, dose-dependent manner. VD₃ also had a significant antifungal effect on the initiation, development, and maturation phases of biofilm formation in Candida albicans. The mechanism of VD₃ action was explored by transcriptomics and reverse transcription quantitative PCR (RT-qPCR) analysis, and showed that VD₃ affects ribosome biogenesis, coenzyme metabolism, and carbon metabolism. These results suggested that VD₃ may have multitarget effects against C. albicans. In the murine IAC model, VD₃ reduced the fungal burden in the liver, kidneys, and small intestine. Further histopathological analysis and quantification of plasma cytokine levels confirmed that VD₃ treatment significantly decreased the infiltration of inflammatory cells and the levels of plasma interferon (IFN)-γ and tumor necrosis factor (TNF)-α. Taken together, these findings suggest a new antifungal mechanism for VD₃ and indicate that VD₃ could be an effective therapeutic agent for use in IAC treatment.

SARS-CoV-2 nucleocapsid protein triggers hyperinflammation via protein-protein interaction-mediated intracellular Cl- accumulation in respiratory epithelium

SARS-CoV-2, the culprit pathogen of COVID-19, elicits prominent immune responses and cytokine storms. Intracellular Cl⁻ is a crucial regulator of host defense, whereas the role of Cl⁻ signaling pathway in modulating pulmonary inflammation associated with SARS-CoV-2 infection remains unclear. By using human respiratory epithelial cell lines, primary cultured human airway epithelial cells, and murine models of viral structural protein stimulation and SARS-CoV-2 direct challenge, we demonstrated that SARS-CoV-2 nucleocapsid (N) protein could interact with Smad3, which downregulated cystic fibrosis transmembrane conductance regulator (CFTR) expression via microRNA-145. The intracellular Cl⁻ concentration ([Cl⁻]_i) was raised, resulting in phosphorylation of serum glucocorticoid regulated kinase 1 (SGK1) and robust inflammatory responses. Inhibition or knockout of SGK1 abrogated the N protein-elicited airway inflammation. Moreover, N protein promoted a sustained elevation of [Cl⁻]_i by depleting intracellular cAMP via upregulation of phosphodiesterase 4 (PDE4). Rolipram, a selective PDE4 inhibitor, countered airway inflammation by reducing [Cl⁻]_i. Our findings suggested that Cl⁻ acted as the crucial pathological second messenger mediating the inflammatory responses after SARS-CoV-2 infection. Targeting the Cl⁻ signaling pathway might be a novel therapeutic strategy for COVID-19.

Perillaldehyde protects against Aspergillus fumigatus keratitis by reducing fungal load and inhibiting inflammatory cytokines and LOX-1

PURPOSE

The purpose of this research was to explore the antifungal and anti-inflammatory effects of perillaldehyde (PAE) in Aspergillus fumigatus (A.fumigatus) keratitis and the underlying mechanism.

METHODS

The biofilm formation, adherence assay, propidium iodide uptake test were used to determine the possible mechanism of PAE in terms of antifungal effects in vitro. The severity of corneal infection was evaluated by clinical scores. The immunofluorescence staining was adopt to detect the number of macrophages in infected corneas. Draize test was performed to assess the ocular toxicity of PAE. Real-time polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), and Western blot reflected the expression of inflammatory cytokines and Lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) in mice corneas and RAW264.7 cells.

RESULTS

PAE was able to inhibit the formation of biofilm, reduce conidial adhesion, and damage the integrity of membranes to exert antifungal activity. In C57BL/6 mice models, PAE alleviated the severity of infected corneas, reduced the recruitment of macrophages and had low ocular toxicity. In addition, the mRNA and protein levels of TNF-α, CCL-2 and LOX-1 could be significantly decreased by the application of PAE after A.fumigatus infection in vivo and in vitro.

CONCLUSION

Our study indicated that PAE protected against A.fumigatus keratitis by reducing fungal load, accumulation of macrophages, and inhibiting the expression of inflammatory cytokines.

Antifungal Activity of Sodium New Houttuyfonate Against Aspergillus fumigatus in vitro and in vivo

Aspergillus fumigatus is an important pathogen causing invasive aspergillosis, which is associated with high morbidity and mortality in immunocompromised people. However, the treatment of A. fumigatus infection is a growing challenge, owing to the limited availability antifungal agents and the continual emergence of drug-resistant strains. Drug repurposing is a potential strategy to solve this current problem. Sodium new houttuyfonate (SNH), derived from houttuynin, extracted from Houttuynia cordata, has anti-bacterial and anti-Candida albicans effects. However, whether it has anti-A. fumigatus activity had not been reported. In this study, the antifungal properties of SNH against A. fumigatus, including the standard strain AF293, itraconazole resistant clinical strains, and voriconazole resistant clinical strains, were evaluated in vitro and in vivo. Moreover, the potential mechanism of SNH was characterized. SNH exhibited significant fungicidal activity toward various A. fumigatus strains. SNH also inhibited fungal growth, sporulation, conidial germination and pigment formation, and biofilm formation. Further investigations revealed that SNH interfered with the A. fumigatus cell steroid synthesis pathway, as indicated by transcriptomic and quantitative real-time polymerase chain reaction analyses, and inhibited ergosterol synthesis, as indicated by cell membrane stress assays and ergosterol quantification. Moreover, daily gastric gavage of SNH significantly decreased the fungal burden in mice with disseminated infection (kidney, liver, and lung) and local tissue damage. In addition, the application of SNH downregulated the production of IL-6 and IL-17A. Together, these findings provided the first confirmation that SNH may be a promising antifungal agent for the treatment of A. fumigatus infection.

Intestinal Infection of Candida albicans: Preventing the Formation of Biofilm by C. albicans and Protecting the Intestinal Epithelial Barrier

The large mortality and morbidity rate of C. albicans infections is a crucial problem in medical mycology. Because the generation of biofilms and drug resistance are growing concerns, the growth of novel antifungal agents and the looking for newer objectives are necessary. In this review, inhibitors of C. albicans biofilm generation and molecular mechanisms of intestinal epithelial barrier protection are elucidated. Recent studies on various transcription elements; quorum-sensing molecules; host responses to adherence; and changes in efflux pumps, enzymes, bud to hyphal transition, and lipid profiles have increased the knowledge of the intricate mechanisms underlying biofilm resistance. In addition, the growth of novel biomaterials with anti-adhesive nature, natural products, drugs, bioactive compounds, proteins, lipids, and carbohydrates are being researched. Recently, more and more attention has been given to various metal nanoparticles that have also appeared as antibiofilm agents in C. albicans. The intestinal epithelial obstacle exerts an crucial effect on keeping intestinal homeostasis and is increasingly associated with various disorders associated with the intestine such as inflammatory bowel disease (IBD), irritable bowel syndrome, metabolic syndrome, allergies, hepatic inflammation, septic shock, etc. However, whether their involvement in the prevention of other intestinal disorders like IBD are useful in C. albicans remains unknown. Further studies must be carried out in order to validate their inhibition functions in intestinal C. albicans. This provides innovates ideas for intestinal C. albicans treatment.

Therapeutic Potential of Perillaldehyde in Ameliorating Vulvovaginal Candidiasis by Reducing Vaginal Oxidative Stress and Apoptosis

Vulvovaginal candidiasis (VVC) is one of the most frequent diseases induced by Candida albicans (C. albicans) during pregnancy, which results in enormous pain to women and their partners in daily life. Perillaldehyde (PAE), a natural monoterpenoid, has significant anti-microbial, anti-inflammatory and anti-oxidation effects. Reactive oxygen species (ROS) are key factors for the host to resist the invasion of fungi. However, excess ROS can cause additional damage independent of the pathogen itself, and the mechanism of ROS in VVC has not been investigated. In this murine study, we revealed that C. albicans infection increased the expression of NADPH oxidase 2 (NOX2) and the content of malonaldehyde (MDA). C. albicans inhibited the activity of antioxidant enzymes in the vagina, including superoxide dismutase (SOD), Catalase (CAT), glutathione peroxidase (GSH-PX) and heme oxygenase (HO-1), which were returned to normal levels after treatment with PAE. Furthermore, PAE inhibited the activities of Keap1 and promoted Nrf2 transfer from cytoplasm to nucleus, which were mediated by excessive accumulation of ROS in the VVC mice. In this study, we also indicated that PAE inhibited the apoptosis of vagina cells via Caspase 9- Caspase 7-PARP pathway and prevented the release of IL-1ꞵ in VVC mice. In summary, this study revealed that the treatment of VVC in mice with PAE might be mediated by inhibition of ROS, and established the therapeutic potential of PAE as an antifungal agent for the treatment of VVC.

Perillaldehyde improves cognitive function in vivo and in vitro by inhibiting neuronal damage via blocking TRPM2/NMDAR pathway

BACKGROUND

Vascular cognitive dysfunction in patients with vascular dementia (VD) is a kind of severe cognitive dysfunction syndrome caused by cerebrovascular diseases. At present, effective drugs to improve the cognitive function of VD patients still need to be explored. Transient Receptor Potential Melastatin 2 (TRPM2) channel is a nonspecific cation channel that plays a key role in the toxic death of neurons. Perillaldehyde (PAE) has the protective effect of epilepsy and insomnia and other central nervous system diseases. The aim of this study is to explore whether PAE improves cognitive function in VD rats and to investigate the potential mechanisms in vivo and vitro.

METHODS

VD rats were induced by bilateral common carotid arteries occlusion (2-vessel occlusion [2VO]) and treated with PAE for 4 weeks. The neuroprotective effects of PAE was subsequently assessed by the Morris water maze, hematoxylin-eosin (HE) staining, Golgi staining, electron microscopy, Neuron-specific nuclear protein (Neu N) staining, and TdT-mediated dUTP nick end labeling (TUNEL) staining. After primary hippocampal neurons were isolated, cell viability was detected by MTT assay and intracellular Ca²⁺ concentration was detected by calcium imaging assay. The content of Nitriteoxide (NO), Malondialdehyde (MDA) and Superoxide dismutase (SOD) activity in serum of rats were observed by Enzyme Linked Immunosorbent Assay (ELISA). Immunohistochemistry, Western blot, and Confocal laser scanning were used to detect the expression levels of N-methyl-D-asprtate receptor-2B (NR2B) and TRPM2.

RESULTS

The results showed that PAE can improve the number and activity of neurons, increase the length and number of dendrites in hippocampus, decrease the Vv value and PE value of neuronal nucleus and mitochondrial structure significantly, increase the s value and L value in nucleus structure, decrease the s value and L value in mitochondrial structure, and improve the learning and memory ability of rats significantly. And PAE can strengthen the ability of antioxidant stress confirmed by increasing the activity of SOD and reducing the production of MDA. The results of western blot, immunohistochemistry and immunofluorescence showed that PAE could reduce the level of TRPM2 and increase the expression of NR2B.

CONCLUSIONS

Taken together, our findings provide evidence that the neuroprotective effects of PAE in VD rats maybe through TRPM2 inhibition and subsequent activation of NMDAR signaling pathway.

Recent development in biological activities and safety concerns of perillaldehyde from perilla plants: A review

Monoterpene Perillaldehyde (PAE) is a major component of the essential oil extracted from perilla plants (Perilla frutescens), which has been used as a leafy vegetable and a medicinal agent. PAE has gained a lot of attention in recent years because of its antifungal and other microbial activities and, human health benefits. PAE has also been used as food additives, perfume ingredients, and traditional medicine concoctions. Biological analyses of PAE have revealed that it has good antioxidant activities and can serve as organic fruit and food preservative. Animal studies indicated potent anticancer, anti-depressant, and anti-inflammatory effects of PAE. Also, PAE is certified "generally recognized as safe" (GRAS) and not mutagenic. However, moderation during usage is advisable, as minor adverse effects are associated with a very high dosage. Despite the newly reported findings, its properties have not been thoroughly summarized and reviewed. Also, clinical trials and official large-scale field applications of PAE in the agricultural sectors are yet to be reported. In this review, updated PAE research progress was provided, focusing on its antifungal and other antimicrobial properties and the mechanisms behind it, phytochemical profile, pharmacological effects, and safety concerns.HighlightsIsolation and recovery techniques of PAE from perilla plants have been developed and improved in recent years.PAE is a potential anti-oxidant and antifungal agent that can be widely used in the food industry.PAE can be developed into drug ingredients for pharmaceutical industries due to its anti-inflammatory, anti-cancer and anti-depressant activities.PAE can be safely used in human when low and moderate dosage is used.