Fungal infections have become clinically challenging owing to the emergence of drug resistance in invasive fungi and the rapid increase in the number of novel pathogens. The development of drug resistance further restricts the use of antifungal agents. Therefore, there is an urgent need to identify alternative treatments for Cryptococcus neoformans (C. neoformans). Disulfiram (DSF) has a good human safety profile and promising applications as an antiviral, antifungal, antiparasitic, and anticancer agent. However, the effect of DSF on Cryptococcus is yet to be thoroughly investigated. This study investigated the antifungal effects and the mechanism of action of DSF against C. neoformans to provide a new theoretical foundation for the treatment of Cryptococcal infections. In vitro studies demonstrated that DSF inhibited Cryptococcus growth at minimum inhibitory concentrations (MICs) ranging from 1.0 to 8.0 μg/mL. Combined antifungal effects have been observed for DSF with 5-fluorocytosine, amphotericin B, terbinafine, or ketoconazole. DSF exerts significant protective effects and synergistic effects combined with 5-FU for Galleria mellonella infected with C. neoformans. Mechanistic investigations showed that DSF dose-dependently inhibited melanin, urease, acetaldehyde dehydrogenase, capsule and biofilm viability of C. neoformans. Further studies indicated that DSF affected C. neoformans by interfering with multiple biological pathways, including replication, metabolism, membrane transport, and biological enzyme activity. Potentially essential targets of these pathways include acetaldehyde dehydrogenase, catalase, ATP-binding cassette transporter (ABC transporter), and iron-sulfur cluster transporter. These findings provide novel insights into the application of DSF and contribute to the understanding of its mechanisms of action in C. neoformans.

OBJECTIVES:Given the challenges posed by toxicity and drug resistance in the treatment of cryptococcal infections, we sought to explore the antifungal potential of verapamil (VER), a calcium channel blocker, against Cryptococcus neoformans (C. neoformans), and its potential synergy with antifungals, specifically caspofungin (CAS). MATERIALS AND METHODS:In vitro and in vivo (Galleria mellonella) models were employed to assess VER's antifungal activity and its interaction with CAS. Mechanisms underlying the synergism were explored through analysis of cell wall integrity, membrane permeability, and gene expression related to the calcineurin pathway. Additionally, the influence of Ca2+ on chitin deacetylase activity was investigated. RESULTS:VER exhibited a pronounced antifungal effect on C. neoformans and synergized with CAS, enhancing antifungal efficacy in Galleria mellonella. VER reduced chitosan content and disrupted cell wall integrity, evidenced by melanin leakage and fluorescence staining. VER+CAS modified membrane permeability, triggering intracellular ROS accumulation and mitochondrial membrane potential alterations. VER mitigated CAS-induced calcium fluctuations and downregulated calcineurin pathway genes. Furthermore, it was found that the enzyme activity of chitin deacetylase of C. neoformans is significantly influenced by the presence of Ca2+, suggesting that the use of VER may affect this activity. CONCLUSIONS:The synergistic antifungal effect of VER and CAS represents a promising therapeutic strategy for cryptococcal infections. The multifaceted mechanisms, including disruption of cell wall integrity and modulation of membrane permeability, and regulation of intracellular calcium signaling pathways, offer new insights into antifungal drug development.

The 3,4-dihydroxyphenylalanine (DOPA) melanin is one of the important virulence factors for Cryptococcus neoformans, which may trigger immune responses in the host. While the production of DOPA melanin is catalyzed by laccase that is predominantly encoded by LAC1 gene. Therefore, regulating the genetic expression of C. neoformans is conducive to exploring the impact of interested molecules on the host. In this work, we established two systems that were constructed quickly and easily for the knock-down/knock-out of LAC1 gene: RNA interference (RNAi) and clustered regularly interspaced short palindromic repeats CRISPR-Cas9. The RNAi system was constructed by pSilencer 4.1-CMV neo plasmid and short hairpin RNA to achieve effective transcriptional suppression. The CRISPR-Cas9 system was used the PNK003 vectors to obtain a stable albino mutant strain. The results of phenotype, quantitative real-time polymerase chain reaction, transmission electron microscope, and spectrophotometry were used to assess the ability of melanin production. As a result, the RNAi system displayed attenuation of transcriptional suppression when the transformants continuously passed on new plates. However, the transcriptional suppression of long loop in short hairpin RNA was more powerful and lasted longer. An albino strain produced by CRISPR-Cas9 was completely unable to synthesize melanin. In conclusion, strains with different capacities of melanin production were obtained by RNAi and CRISPR-Cas9 systems, which might be useful for exploring the linear relation between melanin and immunoreaction of the host. In addition, the two systems in this article might be convenient to quickly screen the possible trait-regulating genes of other serotypes of C. neoformans.

The overuse of antifungal and immunosuppressant drugs and the higher frequency of organ transplantation has resulted in mycosis being increasingly intractable, and there is a great need for the development of new therapies. Melanin is an important virulence factor that can inhibit the inflammatory response in the host and facilitate fungal survival by several methods. However, a recent study showed that the Akt/mTOR/HIF1α axis in macrophages was activated after melanin-binding proteins recognised the DHN melanin of Aspergillus fumigatus, with a resulting metabolic shift towards glycolysis (i.e., metabolic reprogramming). As a result, antimicrobial compounds (e.g., inflammatory mediators and reactive oxygen species) were increased to fight the fungal invasion. Actually, DHN melanin from other fungi and DOPA melanin can induce inflammation and stimulate the production of melanin-binding antibodies. In addition, DOPA melanin contains conserved repeating units that are similar to those of DHN melanin. Therefore, we evaluated the associated evidence to propose an interesting and reasonable hypothesis that melanin promotes inflammation by metabolic reprogramming, which could provide a research direction for antifungal therapy. It suggests that regulating the metabolism of immune cells can guide the inflammatory response against fungi, despite the presence of immunosuppressant melanin. Since the biochemical molecules of glycolysis are clearly described, regulating glycolysis in macrophages may be easier than inventing new antifungal drugs. Further clarification of our hypothesis may strengthen the candidacy of melanin for future antifungal vaccines.

Background The frequent coexistence of obesity and metabolic syndrome in patients with Androgenetic alopecia (AGA), may indicate a common pathogenetic pathway with adipokines being a possible implicating cytokine. Objective This study was conducted to investigate the changes in serum levels of adipokines, insulin resistance, vitamin D status and their relationship with AGA, and the relationship between serum levels of adipokines and insulin resistance. Methods 80 male patients with AGA were selected as the experimental group and 60 healthy males served as the control group. Both the AGA group and healthy control group were divided into 2 groups according to the presence or absence of insulin resistance (IR): the IR group and the NIR group. Serum levels of leptin, adiponectin, resistin, visfatin, insulin and 25(OH)D were evaluated in all subjects. Results Compared with the control group, AGA patients showed higher serum levels of leptin and lower adiponectin/leptin (Adpn/Lep) ratio (P<0.05), and both were positively correlated with the severity of the disease. Compared with the AGA NIR group, serum leptin levels were increased in the AGA IR group (P<0.05). AGA IR group and AGA NIR group possessed lower Adpn/Lep ratio when compared with the healthy IR group and healthy NIR group respectively (P<0.05). The multi-factor logistic regression analysis results showed decreased Adpn/Lep level and increased leptin level as risk factors for AGA. AGA Patients had lower vitamin D levels than healthy controls (P<0.05). Conclusion Patients with AGA show an imbalance between pro- and anti-inflammatory adipokines, and probably be involved in AGA pathogenesis. Insulin resistance may influence levels of adipokines, but the present findings cannot indicate insulin resistance plays a role in the onset of AGA. The insufficiency and deficiency of vitamin D are common health concern in our subjects and may be involved in the dysfunction of adipocytes and the development of AGA.

例1 女，71岁，2020年9月8日因全身红疹伴口唇黏膜破溃7 d于东部战区总医院就诊。2020年8月因右膝关节积液伴疼痛曾于外院静脉滴注地塞米松、口服头孢类药物等。9月2日因消化道出血外院予头孢尼西钠、奥美拉唑及输血等治疗，期间躯干、四肢新发红疹，口唇黏膜破溃，伴瘙痒、高热，予地塞米松、马来酸氯苯那敏、异丙嗪等治疗后热退，但皮损未见明显好转，遂至我院急诊科静脉滴注甲泼尼龙40 mg，以Stevens-Johnson综合征（Stevens-Johnson syndrome，SJS）转入皮肤科。高血压病史15年，口服苯磺酸氨氯地平片（1片/d）治疗，无过敏史。9月7日实验室检查：血红蛋白96 g/L（参考值：115 ~ 150 g/L，下同），C反应蛋白66.7 mg/L（0 ~ 8 mg/L），降钙素原0.109 μg/L（0 ~ 0.046 μg/L），脑利钠肽前体1 277 pmol/L（<106.2 pmol/L），总蛋白54.2 g/L（65 ~ 85 g/L），白蛋白28 g/L（40 ~ 55 g/L），尿素7.7 mmol/L（2 ~ 7.1 mmol/L），抗核抗体谱均阴性，补体C3、C4未见异常。生命体征平稳。皮肤科检查：口唇黏膜破溃结痂，面部、躯干、四肢弥漫暗红色丘疹、斑丘疹，部分表面黑痂（图1A、1B）。初步诊断为SJS。治疗：予单次皮下注射50 mg重组人Ⅱ型肿瘤坏死因子受体—抗体融合蛋白（益赛普）及对症支持治疗。用药24 h内未见新发皮损；8 d后面部、躯干四肢皮损明显消退，遗留部分暗红色结痂（图1E、1F）。治疗期间患者血中性粒细胞计数、淋巴细胞计数、总蛋白、白蛋白有回升趋势；C反应蛋白、降钙素原、脑利钠肽前体、尿素呈下降趋势。淋巴细胞计数、C反应蛋白、降钙素原、尿素治疗8 d后恢复正常。治疗期间无高热或其他并发症。治疗16 d，全身皮疹及结痂基本消退，随访至2021年5月未见复发。

In recent years, the incidence of PCa in China has been increasing year by year. Early diagnosis of the malignancy and monitoring of its progression are keys to the reduction of mortality. Currently, early diagnosis of PCa is mainly achieved by determining the level of PSA. Due to the insufficient specificity of PSA, definite diagnosis necessitates needle biopsy, which, as an invasive procedure, causes injury to the patients. Therefore biomarkers seem to be a significant option for the improvement of diagnostic accuracy. Exosomes are 30－150 nm extracellular vesicles secreted by various types of cells in normal and pathological conditions and exist stably in circumcision. Studies show that exosomes contain miRNAs and proteins critical to the progression and metastasis of PCa and have a great potential in the diagnosis of the malignancy. This review outlines the advances in the application of exosomes as novel biomarkers in the diagnosis of PCa.