Novel Selectively Targeted Multifunctional Nanostructured Lipid Carriers for Prostate Cancer Treatment

Prostate cancer (PC) is the most common cancer in men over 50 and the 4th most prevalent human malignancy. PC treatment may include surgery, androgen deprivation therapy, chemotherapy, and radiation therapy. However, the therapeutic efficacy of systemic chemotherapy is limited due to low drug solubility and insufficient tumor specificity, inflicting toxic side effects and frequently provoking the emergence of drug resistance. Towards the efficacious treatment of PC, we herein developed novel selectively PC-targeted nanoparticles (NPs) harboring a cytotoxic drug cargo. This delivery system is based upon PEGylated nanostructured lipid carriers (NLCs), decorated with a selective ligand, targeted to prostate-specific membrane antigen (PSMA). NPs loaded with cabazitaxel (CTX) displayed a remarkable loading capacity of 168 ± 3 mg drug/g SA-PEG, encapsulation efficiency of 67 ± 1%, and an average diameter of 159 ± 3 nm. The time-course of in vitro drug release from NPs revealed a substantial drug retention profile compared to the unencapsulated drug. These NPs were selectively internalized into target PC cells overexpressing PSMA, and displayed a dose-dependent growth inhibition compared to cells devoid of the PSMA receptor. Remarkably, these targeted NPs exhibited growth-inhibitory activity at pM CTX concentrations, being markedly more potent than the free drug. This selectively targeted nano-delivery platform bears the promise of enhanced efficacy and minimal untoward toxicity.

Novel antifungal activity of Q-Griffithsin, a broad-spectrum antiviral lectin

Background There is a rising global trend in candida strains with high resistance to fluconazole and other antifungal drugs, hence the need for novel agents. Here, we investigated the anti-Candida activity of Q-Griffithsin (Q-GRFT), a lectin naturally produced by the red-sea algae, Griffithsia spp. Methods To assess in vitro growth inhibitory activity, C. albicans was incubated with Q-GRFT on agar plates and in broth media. We investigated GFP-bound Q-GRFT’s ability to adhere to C. albicans using fluorescence microscopy and fluorescence intensity assessments. To demonstrate in vivogrowth inhibitory activity, CBA/J mice were treated per vaginam with Q-GRFT followed by challenge with C. albicans, and fungal burden determined following vaginal lavage. Results Wild type fluorescently labeled Q-GRFT displayed higher fluorescence than the lectin-binding site deficient variant following incubation with C. albicans. Q-GRFT localized around the fungal cells and bound to α-mannan in the cell wall. Q-GRFT significantly inhibited C. albicans growth in broth and on agar plates, disrupted the integrity of the cell wall, and induced ROS formation. The lectin significantly inhibited the growth of C. glabrata, C. parapsilosis and C. krusei, with modest activity against C. auris CDC388 and C. auris CDC389 strains in vitro. Topical treatment resulted in a lower fungal burden compared to the vehicle control group in vaginal candidiasis. Conclusion Q-GRFT binds to and inhibits C. albicans growth both in vitro and in vivo. Further studies are needed to establish the mechanism of growth inhibition.

Comparison of the Antibacterial Activity of Australian Terminalia Spp. Extracts Against Klebsiella Pneumoniae: Novel Treatment for Ankylosing Spondylitis

Traditional medicines prepared using Terminalia species have been used globally to treat inflammation and pathogenic infections. Recent studies have demonstrated that multiple Asian and African Terminalia spp. inhibit bacterial triggers of some autoimmune inflammatory disease, including ankylosing spondylitis. Despite this, the effects of Australian Terminalia spp. on a bacterial trigger of ankylosing spondylitis (K. pneumoniae) remain unexplored. Fifty-five extracts from five Australian Terminalia spp. were investigated for K. pneumoniae growth inhibitory activity. Methanolic, aqueous and ethyl acetate extracts of most species and plant parts inhibited K. pneumoniae growth, with varying potencies. Methanolic leaf extracts were generally the most potent bacterial growth inhibitors, with MIC values of 66 µg/mL (T. ferdinandiana), 128 µg/mL (T. carpenteriae) and 83 µg/mL (T. petiolares). However, the aqueous leaf extract was the most potent T. grandiflora extract (MIC = 87 µg/mL). All T. catappa extracts displayed low growth inhibitory activity. The Terminalia spp. methanolic leaf extracts were examined by LC-MS and GC-MS. All contained a relative abundance of simple gallotannins (particularly gallic and chebulic acids), the flavonoid luteolin, as well as the monoterpenoids cineole and terpineol. Notably, all Terminalia spp. were non-toxic or of low toxicity in ALA and HDF toxicity assays, highlighting their potential for preventing the onset of ankylosing spondylitis and treating its symptoms once the disease is established.

In vitro growth inhibitory activity of Medicines for Malaria Venture pathogen box compounds against Leishmania aethiopica

Introduction Leishmania aethiopica (L. aethiopica) is responsible for different forms of cutaneous leishmaniasis (CL) in Ethiopia. Treatment heavily depends on limited drugs, together with drawbacks like toxicity and microbial resistance. The current research aimed to investigate in vitro growth inhibitory activity of Medicines for Malaria Ventures - Pathogen Box (MMV - PB) compounds against L. aethiopica clinical isolate. Methodology Four hundred MMV – PB compounds were screened against L. aethiopica using resazurin based colourimetric assay. Compounds with > 70% inhibition were further tested using macrophage based intracellular amastigote assay. Cytotoxic and hemolytic activity of candidate hits were assessed on THP1- cells and sheep red blood cells (RBCs), respectively. In vitro drug interaction study was also conducted for the most potent hit using the combination index method. Results At the test concentration of 1 μM, twenty-three compounds showed > 50% inhibition of promastigotes parasite growth, of which 11 compounds showed > 70% inhibition. The 50% growth inhibition (IC50) of the 11 compounds was ranged from 0.024 to 0.483 μM in anti-promastigote assay and from 0.064 to 0.899 μM in intracellular amastigote assay. Candidate compounds demonstrated good safety on sheep RBCs and THP-1 cell lines. MMV688415 demonstrated a slight hemolytic activity on sheep RBC (5.3% at 25 μM) and THP-1 cell line (CC20 = 25 μM) while MMV690102 inhibited half of THP-1 cells at 36.5 μM (selectivity index = 478). No synergistic activity was observed from the combinations of MMV690102 and amphotericin B (CI > 1), and MMV690102 and Pentamidine (CI > 1) at lower and higher combination points. Conclusion The present study identified a panel of compounds that can be used as a novel starting point for lead optimization. MMV690102 appears to be the most potent inhibitor against L. aethiopica promastigotes and amastigotes. Future works should investigate the antileishmanial mechanism of action and in vivo antileishmanial activities of identified hits.

New Bioactive Fused Triazolothiadiazoles as Bcl-2-Targeted Anticancer Agents

A series of 3-(6-substituted phenyl-[1,2,4]-triazolo[3,4-b]-[1,3,4]-thiadiazol-3-yl)-1H-indoles (5a–l) were designed, synthesized and evaluated for anti-apoptotic Bcl-2-inhibitory activity. Synthesis of the target compounds was readily accomplished through a reaction of acyl hydrazide (1) with carbon disulfide in the presence of alcoholic potassium hydroxide to afford the corresponding intermediate potassium thiocarbamate salt (2), which underwent cyclization reaction in the presence of excess hydrazine hydrate to the corresponding triazole thiol (3). Further cyclisation reaction with substituted benzoyl chloride derivatives in the presence of phosphorous oxychloride afforded the final 6-phenyl-indol-3-yl [1,2,4]-triazolo[3,4-b]-[1,3,4]-thiadiazole compounds (5a–l). The novel series showed selective sub-micromolar IC50 growth-inhibitory activity against Bcl-2-expressing human cancer cell lines. The most potent 6-(2,4-dimethoxyphenyl) substituted analogue (5k) showed selective IC50 values of 0.31–0.7 µM against Bcl-2-expressing cell lines without inhibiting the Bcl-2-negative cell line (Jurkat). ELISA binding affinity assay (interruption of Bcl-2-Bim interaction) showed potent binding affinity for (5k) with an IC50 value of 0.32 µM. Moreover, it fulfils drug likeness criteria as a promising drug candidate.

Reversal of ABCG2/BCRP-Mediated Multidrug Resistance by 5,3′,5′-Trihydroxy-3,6,7,4′-tetramethoxyflavone Isolated from the Australian Desert Plant Eremophila galeata Chinnock

Multidrug resistance (MDR) is a major challenge in cancer treatment, and the breast cancer resistance protein (BCRP) is an important target in the search for new MDR-reversing drugs. With the aim of discovering new potential BCRP inhibitors, the crude extract of leaves of Eremophila galeata, a plant endemic to Australia, was investigated for inhibitory activity of parental (HT29par) as well as BCRP-overexpressing HT29 colon cancer cells resistant to the chemotherapeutic SN-38 (i.e., HT29SN38 cells). This identified a fraction, eluted with 40% acetonitrile on a solid-phase extraction column, which showed weak growth-inhibitory activity on HT29SN38 cells when administered alone, but exhibited concentration-dependent growth inhibition when administered in combination with SN-38. The major constituent in this fraction was isolated and found to be 5,3′,5′-trihydroxy-3,6,7,4′-tetramethoxyflavone (2), which at a concentration of 25 μg/mL potentiated the growth-inhibitory activity of SN-38 to a degree comparable to that of the known BCRP inhibitor Ko143 at 1 μM. A dye accumulation experiment suggested that 2 inhibits BCRP, and docking studies showed that 2 binds to the same BCRP site as SN-38. These results indicate that 2 acts synergistically with SN-38, with 2 being a BCRP efflux pump inhibitor while SN-38 inhibits topoisomerase-1.

Chemical composition and anticancer effects of Hyptis Suaveolens L. Poit (lamiaceae) volatile oil

The leaf of Hyptis suaveolens have found application in ethnomedicine in the treatment of various ailments including those that are related to tumor and cancer. This study was therefore undertaken to evaluate the cytotoxic effects of its volatile oil. Volatile oil distilled from freshly collected leaves using a Clavenger-type apparatus was screened using tadpoles of Raniceps ranninus (10-40 µg/mL) and brine shrimp of Artemia salina (10-1000 µg/mL) with bench-top assay procedures for cytotoxicity while growth inhibitory activity was assessed using radicles of Sorghum bicolor seeds (1-30 mg/mL). The essential oils were further tested on breast cancer (AU 565) and cervical cancer (HeLa) at 50 µg /mL using 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay and afterwards subjected to Gas Chromatography Mass Spectrometric (GCMS) analysis for its constituents. An LC50 of 188.67 and 8 µg/mL were obtained in the brine shrimp mortality and tadpole lethality assays respectively. The oil showed inhibitions of 86.74 and 21.8 % against AU 565 and HeLa cells respectively. GCMS analysis revealed the major constituents as sabinene (10.64 %) and (-)-4-terpineol (7.27 %). These results support its use in treating tumor-related ailments and should be considered for further studies.

Distribution of Growth-inhibitory Activity, Mineral Contents, and Functional Components in Different Tissue Parts of Asparagus (Asparagus officinalis L.) and Availability of Unusable Parts

Asparagus is a popular vegetable rich in healthy functional components. However, the process of its production leaves ferns from aboveground parts and roots from underground parts as unusable parts, and this is an issue to be resolved. In our previous studies, large amounts of rutin were noted in the cladophylls and storage roots (brown and epidermis), and the protodioscin content was high in buds, in the soil-covered section of spears, and in rhizomes. This study was conducted to examine the distribution of growth-inhibitory activity and mineral contents in different parts of asparagus. Correlations, including representative functional components (rutin and protodioscin), were examined. The results suggest there are differences in growth-inhibitory activity of different parts of asparagus. The growth-inhibitory activity was strong in the buds, rhizome, and absorptive and storage roots, and weak in the cladophylls and lateral branches. The percent N content of the aboveground part of asparagus was high compared with that in the aboveground part of other crops. Although the percent K content was similar to the mean of the aboveground part of other crops, it was higher than that in general green manure, suggesting the residual stems and leaves of the aboveground part of asparagus are effective green manure. In the aboveground part of asparagus, the rutin content and percent N and K content were higher, whereas growth-inhibitory activity tended to be low, suggesting that when no disease developed in the aboveground part, it can be used as an organic substance.

Whole-Genome Sequencing of Alcaligenes faecalis HZ01, with Potential to Inhibit Nontuberculous Mycobacterial Growth

Alcaligenes faecalis is a Gram-negative rod that is ubiquitous in the environment and is an opportunistic human pathogen. Here, we report the whole-genome sequencing analysis of A. faecalis HZ01, which presents mycobacterial growth inhibitory activity and was isolated from a contaminated culture of Mycobacterium chubuense ATCC 27278.