Natural alkaloid tryptanthrin exhibits novel anticryptococcal activity.

Cryptococcal meningitis is a prevalent invasive fungal infection that causes around 180 000 deaths annually. Currently, treatment for cryptococcal meningitis is limited and new therapeutic options are needed. Historically, medicinal plants are used to treat infectious and inflammatory skin infections. Tryptanthrin is a natural product commonly found in these plants. In this study, we demonstrated that tryptanthrin had antifungal activity with minimum inhibitory concentration (MIC) of 2 µg/ml against Cryptococcus species and of 8 µg/ml against Trichophyton rubrum. Further analysis demonstrated that tryptanthrin exerted fungistatic and potent antifungal activity at elevated temperature. In addition, tryptanthrin exhibited a synergistic effect with the calcineurin inhibitors FK506 and cyclosporine A against Cryptococcus neoformans. Furthermore, our data showed that tryptanthrin induced cell cycle arrest at the G1/S phase by regulating the expression of genes encoding cyclins and the SBF/MBF complex (CLN1, MBS1, PCL1, and WHI5) in C. neoformans. Screening of a C. neoformans mutant library further revealed that tryptanthrin was associated with various transporters and signaling pathways such as the calcium transporter (Pmc1) and protein kinase A signaling pathway. In conclusion, tryptanthrin exerted novel antifungal activity against Cryptococcus species through a mechanism that interferes with the cell cycle and signaling pathways. LAY SUMMARY: The natural product tryptanthrin had antifungal activity against Cryptococcus species by interfering cell cycle and exerted synergistic effects with immunosuppressants FK506 and cyclosporine A. Our findings suggest that tryptanthrin may be a potential drug or adjuvant for the treatment of cryptococcosis.

Deletion of ADA2 Increases Antifungal Drug Susceptibility and Virulence in Candida glabrata.

Candida glabrata, the second most frequent cause of candidiasis after Candida albicans, is an emerging human fungal pathogen that is intrinsically drug tolerant. Currently, studies of C. glabrata genes involved in drug tolerance are limited. Ada2, a component serving as a transcription adaptor of the Spt-Ada-Gcn5 acetyltransferase (SAGA) complex, is required for antifungal drug tolerance and virulence in C. albicans However, its roles in C. glabrata remain elusive. In this study, we found that ada2 mutants demonstrated severe growth defects at 40°C but only mild defects at 37°C or 25°C. In addition, C. glabrata ada2 mutants exhibited pleiotropic phenotypes, including susceptibility to three classes of antifungal drugs (i.e., azoles, echinocandins, and polyenes) and cell wall-perturbing agents but resistance to the endoplasmic reticulum stressor tunicamycin. According to RNA sequence analysis, the expression of 43 genes was downregulated and the expression of 442 genes was upregulated in the ada2 mutant compared to their expression in the wild type. C. glabrata ADA2, along with its downstream target ERG6, controls antifungal drug tolerance and cell wall integrity. Surprisingly, ada2 mutants were hypervirulent in a murine model of systemic infection, possibly due to the upregulation of multiple adhesin-like genes, increased agar invasion, and overstimulation of murine tumor necrosis factor alpha production.

In Silico Investigation of Traditional Chinese Medicine for Potential Lead Compounds as SPG7 Inhibitors against Coronary Artery Disease.

Coronary artery disease (CAD) is the most common cause of heart attack and the leading cause of mortality in the world. It is associated with mitochondrial dysfunction and increased level of reactive oxygen species production. According to the Ottawa Heart Genomics Study genome-wide association study, a recent research identified that Q688 spastic paraplegia 7 (SPG7) variant is associated with CAD as it bypasses the regulation of tyrosine phosphorylation of AFG3L2 and enhances the processing and maturation of SPG7 protein. This study aims to identify potential compounds isolated from Traditional Chinese Medicines (TCMs) as potential lead compounds for paraplegin (SPG7) inhibitors. For the crystallographic structure of paraplegin, the disordered disposition of key amino acids in the binding site was predicted using the PONDR-Fit protocol before virtual screening. The TCM compounds saussureamine C and 3-(2-carboxyphenyl)-4(3H)-quinazolinone, have potential binding affinities with stable H-bonds and hydrophobic contacts with key residues of paraplegin. A molecular dynamics simulation was performed to validate the stability of the interactions between each candidate and paraplegin under dynamic conditions. Hence, we propose these compounds as potential candidates as lead drug from the compounds isolated from TCM for further study in drug development process with paraplegin protein for coronary artery disease.

Calcineurin signaling: lessons from Candida species.

Human fungal infections have significantly increased in recent years due to the emergence of immunocompromised patients with AIDS and cancer. Among them, Candida species are frequently isolated and associated with high mortality if not appropriately treated. Current antifungal drugs (azoles, echinocandins and polyenes) are not sufficient to combat Candida species particularly those that are drug resistant. Calcineurin, a calcium/calmodulin-dependent protein phosphatase, is an attractive antifungal drug target, and its inhibitor (FK506 or cyclosporin A) can be combined with azoles or echinocandins for use against multidrug-resistant Candida species. The role of calcineurin in the hyphal growth of Candida albicans is controversial, but its roles in C. dubliniensis, C. tropicalis and C. lusitaniae can be demonstrated. In addition, calcineurin is required for virulence of Candida species in murine systemic, ocular or urinary infection models. However, the requirement for calcineurin substrate Crz1 in these infection models varies in Candida species, suggesting that Crz1 has diverse functions in different Candida species. Besides being critical for growth in serum of Candida species, calcineurin is critical for plasma membrane integrity and growth at body temperature (37°C) uniquely in C. glabrata, suggesting that Candida calcineurin controls pathogenesis via various novel mechanisms. In this review, we summarize studies of calcineurin signaling and hyphal growth, virulence and its relationship with drug tolerance in Candida species, focusing on the divergent and conserved functions.

Calcineurin controls hyphal growth, virulence, and drug tolerance of Candida tropicalis.

Candida tropicalis, a species closely related to Candida albicans, is an emerging fungal pathogen associated with high mortality rates of 40 to 70%. Like C. albicans and Candida dubliniensis, C. tropicalis is able to form germ tubes, pseudohyphae, and hyphae, but the genes involved in hyphal growth machinery and virulence remain unclear in C. tropicalis. Recently, echinocandin- and azole-resistant C. tropicalis isolates have frequently been isolated from various patients around the world, making treatment difficult. However, studies of the C. tropicalis genes involved in drug tolerance are limited. Here, we investigated the roles of calcineurin and its potential target, Crz1, for core stress responses and pathogenesis in C. tropicalis. We demonstrate that calcineurin and Crz1 are required for hyphal growth, micafungin tolerance, and virulence in a murine systemic infection model, while calcineurin but not Crz1 is essential for tolerance of azoles, caspofungin, anidulafungin, and cell wall-perturbing agents, suggesting that calcineurin has both Crz1-dependent and -independent functions in C. tropicalis. In addition, we found that calcineurin and Crz1 have opposite roles in controlling calcium tolerance. Calcineurin serves as a negative regulator, while Crz1 plays a positive role for calcium tolerance in C. tropicalis.

Serum hyperglycemia might be not related to fat composition of diet and vegetable composition of diet might improve sugar control in taiwanese diabetic subjects.

OBJECTIVE: This is an Asian study, which was designed to examine the correlations between biochemical data and food composition of diabetic patients in Taiwan. METHODS: One hundred and seventy Taiwanese diabetic patients were enrolled. The correlations between biochemical data and diet composition (from 24-hour recall of intake food) of these patients were explored (Spearman correlation, p < 0.05). Diet components were also correlated with each other to show diet characteristics of diabetic patients in Taiwan. Linear regression was also performed for the significantly correlated groups to estimate possible impacts from diet composition to biochemical data. RESULTS: Postprandial serum glucose level was negatively correlated with fat percentage of diet, intake amount of polyunsaturated fatty acid and fiber diet composition. Hemoglobin A1c was negatively correlated with fat diet, polyunsaturated fatty acid and vegetable diet. Fat composition, calorie percentage accounted by polyunsaturated fatty acid and monounsaturated fatty acid in diet seemed to be negatively correlated with sugar percentage of diet and positively correlated with vegetable and fiber composition of diet. Linear regression showed that intake amount of polyunsaturated fatty acid, calorie percentage accounted by polyunsaturated fatty acid, fat percentage of diet, vegetable composition of diet would predict lower hemoglobin A1c and postprandial blood sugar. Besides, higher percentage of fat diet composition could predict higher percentage of vegetable diet composition in Taiwanese diabetic patients. CONCLUSION: Fat diet might not elevate serum glucose. Vegetable diet and polyunsaturated fatty acid diet composition might be correlated with better sugar control in Taiwanese diabetic patients.

Characterization of four new cycloartane triterpenoids from Swietenia macrophylla and their angiotensin-I-converting enzyme inhibitory activity.

Angiotensin I-converting enzyme (ACE) inhibition is currently a common method for the treatment and control of hypertension. In this study, four new (1-4) and one known (5) cycloartane triterpenoids were isolated from the leaves of Swietenia macrophylla by chromatographic techniques and identified by their spectroscopic data and a comprehensive comparison of published data. The triterpenoids were evaluated for their ACE inhibitory potential using in vitro inhibition assays and in silico methods. The inhibition assay and enzyme kinetics results showed that the most active triterpenoid, compound 4, inhibited ACE in a mixed-type manner with an IC50 value of 57.7 ± 6.07 µM. Computer simulations revealed that compound 4 reduces the catalytic efficiency of ACE by competitive insertion into the active pocket blocking the substrate, and the binding activity occurs mainly through hydrogen bonds and hydrophobic interactions. The study showed that S. macrophylla can be a source of bioactive material and the ACE inhibitory triterpenoid could be a potential antihypertensive agent.

Identification of a PD-L1+Tim-1+ iNKT subset that protects against fine particulate matter-induced airway inflammation.

Although air pollutants such as fine particulate matter (PM2.5) are associated with acute and chronic lung inflammation, the etiology of PM2.5-induced airway inflammation remains poorly understood. Here we report that PM2.5 triggered airway hyperreactivity (AHR) and neutrophilic inflammation with concomitant increases in Th1 and Th17 responses and epithelial cell apoptosis. We found that γδ T cells promoted neutrophilic inflammation and AHR through IL-17A. Unexpectedly, we found that invariant natural killer T (iNKT) cells played a protective role in PM2.5-induced pulmonary inflammation. Specifically, PM2.5 activated a suppressive CD4- iNKT cell subset that coexpressed Tim-1 and programmed cell death ligand 1 (PD-L1). Activation of this suppressive subset was mediated by Tim-1 recognition of phosphatidylserine on apoptotic cells. The suppressive iNKT subset inhibited γδ T cell expansion and intrinsic IL-17A production, and the inhibitory effects of iNKT cells on the cytokine-producing capacity of γδ T cells were mediated in part by PD-1/PD-L1 signaling. Taken together, our findings underscore a pathogenic role for IL-17A-producing γδ T cells in PM2.5-elicited inflammation and identify PD-L1+Tim-1+CD4- iNKT cells as a protective subset that prevents PM2.5-induced AHR and neutrophilia by inhibiting γδ T cell function.

Deviation of Trypsin Activity Using Peptide Conformational Imprints.

In this study, a methodology utilizing peptide conformational imprints (PCIs) as a tool to specifically immobilize porcine pancreatic alpha-trypsin (PPT) at a targeted position is demonstrated. Owing to the fabrication of segment-mediated PCIs on the magnetic particles (PCIMPs), elegant cavities complementary to the PPT structure are constructed. Based on the sequence on targeted PPT, the individual region of the enzyme is trapped with different template-derived PCIMPs to show certain types of inhibition. Upon hydrolysis, N-benzoyl-L-arginine ethyl ester (BAEE) is employed to assess the hydrolytic activity of PCIMPs bound to the trypsin using high-performance liquid chromatography (HPLC) analysis. Further, the kinetic data of four different PCIMPs are compared. As a result, the PCIMPs presented non-competitive inhibition toward trypsin, according to the Lineweaver-Burk plot. Further, the kinetic analysis confirmed that the best parameters of PPT/PCIMPs 233-245+G were Vmax = 1.47 × 10-3 mM s-1, Km = 0.42 mM, kcat = 1.16 s-1, and kcat/Km = 2.79 mM-1 s-1. As PPT is bound tightly to the correct position, its catalytic activities could be sustained. Additionally, our findings stated that the immobilized PPT could maintain stable activity even after four successive cycles.

Biological control of potato common scab by Bacillus amyloliquefaciens Ba01.

Potato common scab, which is caused by soil-borne Streptomyces species, is a severe plant disease that results in a significant reduction in the economic value of potatoes worldwide. Due to the lack of efficacious pesticides, crop rotations, and resistant potato cultivars against the disease, we investigated whether biological control can serve as an alternative approach. In this study, multiple Bacillus species were isolated from healthy potato tubers, and Bacillus amyloliquefaciens Ba01 was chosen for further analyses based on its potency against the potato common scab pathogen Streptomyces scabies. Ba01 inhibited the growth and sporulation of S. scabies and secreted secondary metabolites such as surfactin, iturin A, and fengycin with potential activity against S. scabies as determined by imaging mass spectrometry. In pot assays, the disease severity of potato common scab decreased from 55.6 ± 11.1% (inoculated with S. scabies only) to 4.2 ± 1.4% (inoculated with S. scabies and Ba01). In the field trial, the disease severity of potato common scab was reduced from 14.4 ± 2.9% (naturally occurring) to 5.6 ± 1.1% after Ba01 treatment, representing evidence that Bacillus species control potato common scab in nature.

New facets of antifungal therapy.

Invasive fungal infections remain a major cause of morbidity and mortality in immunocompromised patients, and such infections are a substantial burden to healthcare systems around the world. However, the clinically available armamentarium for invasive fungal diseases is limited to 3 main classes (i.e., polyenes, triazoles, and echinocandins), and each has defined limitations related to spectrum of activity, development of resistance, and toxicity. Further, current antifungal therapies are hampered by limited clinical efficacy, high rates of toxicity, and significant variability in pharmacokinetic properties. New antifungal agents, new formulations, and novel combination regimens may improve the care of patients in the future by providing improved strategies to combat challenges associated with currently available antifungal agents. Likewise, therapeutic drug monitoring may be helpful, but its present use remains controversial due to the lack of available data. This article discusses new facets of antifungal therapy with a focus on new antifungal formulations and the synergistic effects between drugs used in combination therapy.

[Clinical research of chloasma treated with the meridian cosmetology and the impacts on estrogen and progestin].

OBJECTIVE: To observe the efficacy difference between meridian cosmetology and western medicine in the treatment of chloasma and explore the impacts of meridian cosmetology on E2 and PRGE. METHODS: Three hundreds cases of chloasma were randomized into a meridian cosmetology group and a western medication group according to the visit sequence, 150 cases in each one. In the meridian cosmetology group, the meridian regulation, acupuncture based on pattern/syndrome differentiation [at the body acupoints such as Qihai (CV 6), Xuehai (SP 10), Zusanli (ST 36), Sanyinjiao (SP 6), Ganshu (BL 18), Pishu (BL 20) and Shenshu (BL 23), etc.] and the local surrounding needling therapy on the chloasma skin lesion were adopted. In the western medication group, the oral administration of Vitamin C and E was prescribed for 3 months. The clinical efficacy was observed for the patients in the two groups. Additionally, 30 cases were collected from the meridian cosmetology group randomly for the detection of estrogen (E2) and progestin (PRGE) before and after treatment. RESULTS: The effective rate in the meridian cosmetology group was 92.6% (126/136), which was superior to 67.0% (75/112) in the western medication group (P < 0.05). For the patients collected from the meridian cosmetology group, as compared with that before treatment, E2 level was decreased (P < 0.01) and PRGE level was increased (P < 0.05). CONCLUSION: The meridian cosmetology achieves the superior efficacy as compared with the western medication group for the chloasma and it can regulate the levels of E2 and PRGE.