Cytotoxicity of lapachol metabolites produced by probiotics

The Clinical Efficacy of Lapachol in Facial Redness Reduction

BACKGROUND

Facial erythema from acne, vascular rosacea, or photoaging is a common difficult-to-treat dermatologic challenge.

OBJECTIVE

The objective of this study was to examine the role of lapachol in alleviating facial erythema associated with a variety of common dermatologic conditions.

METHODS

Twenty-five healthy female and male subjects 35-65 years of age of Fitzpatrick skin types I-II with mild-to-moderate stable facial erythema from acne, rosacea or photoaging were enrolled in a single-site monadic study. Subjects received the study cream for twice daily application and were assessed at baseline, Week 4, and Week 8. The dermatologist investigator and subjects assessed efficacy and tolerability and facial photographic images were taken of all subjects at each visit. Noninvasive erythema assessments of the face were conducted using a colorimeter at baseline, Week 4, and Week 8 to document improvement in facial erythema.

RESULTS

Twenty-five out of 25 subjects successfully completed the study without tolerability issues including 12 subjects with rosacea, 6 subjects with photoaging and 7 subjects with acne. After 8 weeks of use, the investigator rated a 44% decrease in facial erythema while the subjects rated a 40% decrease. Facial erythema was also noninvasively assessed with a colorimeter and dermaspectrophotometer (DSP). There was a 26% decrease in skin redness at Week 4 and a 31% decrease in skin redness at Week 8 on the colorimeter L*a*b* scale. This finding was collaborated by the DSP which registered a 29% decrease on the erythema scale at Week 8.

CONCLUSION

Lapachol in a moisturizer formulation was found to be effective in reducing facial erythema from acne, rosacea, and photoaging.

Chemoprotective and immunomodulatory potential of Lactobacillus reuteri against cadmium chloride-induced breast cancer in mice

INTRODUCTION

The current study aimed to investigate the role of probiotic Lactobacillus reuteri for the treatment and prevention of breast cancer.

MATERIALS AND METHODS

Breast cancer was induced by using Cadmium Chloride (Cd) (2 mg/kg) in group II. Tamoxifen was administered to group III. Group IV was treated with Lactobacillus reuteri. Group V was treated with Cd for one month and divided into three subgroups including VA, VB, and VC which were treated with tamoxifen, Lactobacillus reuteri, and tamoxifen + Lactobacillus reuteri, respectively.

RESULTS

Significantly higher levels of TNF-α (40.9 ± 4.2 pg/mL), IL-6 (28.0 ± 1.5 pg/mL), IL-10 (60.2 ± 2.0 pg/mL), IFN-γ (60.2 ± 2.0 pg/mL), ALAT (167.2 ± 6.2 U/l), ASAT (451.6 ± 13.9 U/l), and MDA (553.8 ± 19.6 U/l) was observed in Cd group. In comparison, significantly lower levels of TNF-α (18.0 ± 1.1 pg/mL), IL-6 (9.4 ± 0.4 pg/mL), IL-10 (20.8 ± 1.1 pg/mL), IFN-γ (20.8 ± 1.1 pg/mL), ALAT (85.2 ± 3.6 U/l), ASAT (185 ± 6.9 U/l), and MDA (246.0 ± 7.5 U/l) were observed in group Cd + Tam + LR. Liver histopathology of the Cd group showed hemorrhage and ductal aberrations. However, mild inflammation and healthier branched ducts were observed in treatment groups. Furthermore, the renal control group showed normal glomerular tufts, chronic inflammation from the Cd group, and relatively healthier glomerulus with mild inflammation in treatment groups.

CONCLUSION

Hence, the preventive and anticancerous role of probiotic Lactobacillus reuteri is endorsed by the findings of the current study.

Microbial Therapy and Breast Cancer Management: Exploring Mechanisms, Clinical Efficacy, and Integration within the One Health Approach

This comprehensive review elucidates the profound relationship between the human microbiome and breast cancer management. Recent findings highlight the significance of microbial alterations in tissue, such as the gut and the breast, and their role in influencing the breast cancer risk, development, progression, and treatment outcomes. We delve into how the gut microbiome can modulate systemic inflammatory responses and estrogen levels, thereby impacting cancer initiation and therapeutic drug efficacy. Furthermore, we explore the unique microbial diversity within breast tissue, indicating potential imbalances brought about by cancer and highlighting specific microbes as promising therapeutic targets. Emphasizing a holistic One Health approach, this review underscores the importance of integrating insights from human, animal, and environmental health to gain a deeper understanding of the complex microbe-cancer interplay. As the field advances, the strategic manipulation of the microbiome and its metabolites presents innovative prospects for the enhancement of cancer diagnostics and therapeutics. However, rigorous clinical trials remain essential to confirm the potential of microbiota-based interventions in breast cancer management.

Therapeutic and immunomodulatory role of probiotics in breast cancer: A mechanistic review

Breast cancer has become the most prevalent and noxious type of malignancy around the globe (Giaquinto et al., 2022). Multiple clinical strategies including chemotherapy, radiotherapy, and immunotherapy have been in practice to manage breast cancer. Besides the protective roles of conventional remedial approaches, and non-reversible and deteriorative impacts like healthy cell damage, organ failure, etc., the world scientific community is in a continuous struggle to find some alternative biocompatible and comparatively safe solutions. Among novel breast cancer management/treatment options, the role of probiotics has become immensely important. The current review encompasses the prevalence statistics of breast cancer across the globe concerning developed and undeveloped counties, intestinal microbiota linkage with breast cancer, and association of breast microbiome with breast carcinoma. Furthermore, this review also narrates the role of probiotics against breast cancer and their mode of action. In Vivo and In Vitro studies under breast cancer research regarding probiotics are mechanistically explained. The current review systematically explains the immunomodulatory role of probiotics to prevent breast cancer. Last, but not the least, current review concludes the use of probiotics in the treatment of breast cancer through various mechanisms and future recommendations for molecular basis studies.

Salt stress perception and metabolic regulation network analysis of a marine probiotic Meyerozyma guilliermondii GXDK6

Introduction

Extremely salt-tolerant microorganisms play an important role in the development of functional metabolites or drug molecules.

Methods

In this work, the salt stress perception and metabolic regulation network of a marine probiotic Meyerozyma guilliermondii GXDK6 were investigated using integrative omics technology.

Results

Results indicated that GXDK6 could accept the salt stress signals from signal transduction proteins (e.g., phosphorelay intermediate protein YPD1), thereby contributing to regulating the differential expression of its relevant genes (e.g., CTT1, SOD) and proteins (e.g., catalase, superoxide dismutase) in response to salt stress, and increasing the salt-tolerant viability of GXDK6. Omics data also suggested that the transcription (e.g., SMD2), translation (e.g., MRPL1), and protein synthesis and processing (e.g., inner membrane protein OXA1) of upregulated RNAs may contribute to increasing the salt-tolerant survivability of GXDK6 by improving protein transport activity (e.g., Small nuclear ribonucleoprotein Sm D2), anti-apoptotic ability (e.g., 54S ribosomal protein L1), and antioxidant activity (e.g., superoxide dismutase). Moreover, up to 65.9% of the differentially expressed genes/proteins could stimulate GXDK6 to biosynthesize many salt tolerant-related metabolites (e.g., β-alanine, D-mannose) and drug molecules (e.g., deoxyspergualin, calcitriol), and were involved in the metabolic regulation of GXDK6 under high NaCl stress.

Discussion

This study provided new insights into the exploration of novel functional products and/or drugs from extremely salt-tolerant microorganisms.Graphical Abstract.

Antifungal Activity of Cell-Free Filtrate of Probiotic Bacteria Lactobacillus rhamnosus ATCC-7469 against Fungal Strains Isolated from a Historical Manuscript

Herein, twelve fungal strains were isolated from a deteriorated historical manuscript dated back to the 18th century. The obtained fungal strains were identified, using the traditional method and ITS sequence analysis, as Cladosporium herbarum (two strains), Aspergillus fumigatus (five strains), A. ustus (one strain), A. flavus (two strains), A. niger (one strain), and Penicillium chrysogenum (one strain). The ability of these fungal strains to degrade the main components of the paper was investigated by their activity to secrete extracellular enzymes including cellulase, amylase, gelatinase, and pectinase. The cell-free filtrate (CFF) ability of the probiotic bacterial strain Lactobacillus rhamnosus ATCC-7469 to inhibit fungal growth was investigated. The metabolic profile of CFF was detected by GC-MS analysis, which confirmed the low and high molecular weight of various active chemical compounds. The safe dose to be used for the biocontrol of fungal growth was selected by investigating the biocompatibility of CFF and two normal cell lines, Wi38 (normal lung tissue) and HFB4 (normal human skin melanocyte). Data showed that the CFF has a cytotoxic effect against the two normal cell lines at high concentrations, with IC₅₀ values of 525.2 ± 9.8 and 329.1 ± 4.2 µg mL^-1 for Wi38 and HFB4, respectively. The antifungal activity showed that the CFF has promising activity against all fungal strains in a concentration-dependent manner. The highest antifungal activity (100%) was recorded for a concentration of 300 µg mL^-1 with a zone of inhibition (ZOI) in the ranges of 21.3 ± 0.6 to 17.7 ± 0.5 mm. At a concentration of 100 µg mL^-1, the activity of CFF remained effective against all fungal strains (100%), but its effectiveness decreased to only inhibit the growth of eight strains (66%) out of the total at 50 µg mL^-1. In general, probiotic bacterial strains containing CFF are safe and can be considered as a potential option for inhibiting the growth of various fungal strains. It is recommended that they be used in the preservation of degraded historical papers.

Biotransformation of hydroxychloroquine to evaluate the cytotoxicity of its metabolites and mimic mammalian metabolism

Hydroxychloroquine (HCQ) displays attractive anti-inflammatory and antiviral effects. Because of that, such a drug made part of some clinical trials for combating Sars-CoV-2 during the COVID-19 pandemic. The present study aimed to conduct the biotransformation of HCQ by filamentous fungi reported as microbial models of mammalian drug metabolism to evaluate its cytotoxic after metabolization. Cunninghamella echinulata var. elegans ATCC 8688a could efficiently biotransform HCQ into one main metabolite identified as the new 4-(1,2,3,4-tetrahydroquinolin-4-ylamino)pentan-1-ol (HCQ-M). The microbial transformation occurred through N-dealkylation, 7-chloro-elimination, and reduction of the two conjugated double-bond from the quinoline system of HCQ. The cytotoxic profiles of HCQ and its metabolite were evaluated using CCD-1059Sk cells (human fibroblasts) through sulforhodamine B, trypan blue, and Live/Dead assays. Both HCQ and HCQ-M displayed cytotoxic activities in human fibroblasts, but HCQ-M was significantly more toxic than HCQ. The reported findings should be considered for further clinical studies of HCQ and will be important for guidance in achieving new derivatives from it.

Probiotics for the Chemoprotective Role against the Toxic Effect of Cancer Chemotherapy

BACKGROUND

Chemo- and radiation therapy-based clinical management of different types of cancers is associated with toxicity and several side effects. Therefore, there is always an unmet need to explore agents that reduce such risk factors. Among these, natural products have attracted much attention because of their potent antioxidant and antitumor effects. In the past, some breakthrough outcomes established that various bacteria in the human intestinal gut are bearing growth-promoting attributes and suppressing the conversion of pro-carcinogens into carcinogens. Hence probiotics integrated approaches are nowadays being explored as rationalized therapeutics in the clinical management of cancer.

METHODS

Here, published literature was explored to review chemoprotective roles of probiotics against toxic and side effects of chemotherapeutics.

RESULTS

Apart from excellent anti-cancer abilities, probiotics alleviate toxicity & side effects of chemotherapeutics, with a high degree of safety and efficiency.

CONCLUSION

Preclinical and clinical evidence suggests that due to the chemoprotective roles of probiotics against side effects and toxicity of chemotherapeutics, their integration in chemotherapy would be a judicious approach.

A Novel Ruthenium(II) Complex With Lapachol Induces G2/M Phase Arrest Through Aurora-B Kinase Down-Regulation and ROS-Mediated Apoptosis in Human Prostate Adenocarcinoma Cells

Lapachol is a well-studied natural product that has been receiving great interest due to its anticancer properties that target oxidative stress. In the present work, two novel lapachol-containing ruthenium(II) complexes [Ru(Lap)(dppm)(bipy)]PF6 (1) and [Ru(Lap)(dppm)(phen)]PF6 (2) [Lap = lapachol, dppm = 1,1'-bis(diphosphino)methane, bipy = 2,2'-bipyridine, phen = 1,10-phenantroline] were synthesized, fully characterized, and investigated for their cellular and molecular responses on cancer cell lines. We found that both complexes exhibited a potent cytotoxic effect in a panel of cancer cell lines in monolayer cultures, as well as in a 3D model of multicellular spheroids formed from DU-145 human prostate adenocarcinoma cells. Furthermore, the complex (2) suppressed the colony formation, induced G2/M-phase arrest, and downregulated Aurora-B. The mechanism studies suggest that complex (2) stimulate the overproduction of reactive oxygen species (ROS) and triggers caspase-dependent apoptosis as a result of changes in expression of several genes related to cell proliferation and caspase-3 and -9 activation. Interestingly, we found that N-acetyl-L-cysteine, a ROS scavenger, suppressed the generation of intracellular ROS induced by complex (2), and decreased its cytotoxicity, indicating that ROS-mediated DNA damage leads the DU-145 cells into apoptosis. Overall, we highlighted that coordination of lapachol to phosphinic ruthenium(II) compounds considerably improves the antiproliferative activities of resulting complexes granting attractive selectivity to human prostate adenocarcinoma cells. The DNA damage response to ROS seems to be involved in the induction of caspase-mediated cell death that plays an important role in the complexes' cytotoxicity. Upon further investigations, this novel class of lapachol-containing ruthenium(II) complexes might indicate promising chemotherapeutic agents for prostate cancer therapy.

Antituberculosis Activities of Lapachol and β-Lapachone in Combination with Other Drugs in Acidic pH

Background: The treatment of multidrug-resistant tuberculosis (MDR-TB) is a challenge to be overcome. The increase of resistant isolates associated with serious side effects during therapy leads to the search for substances that have anti-TB activity, which make treatment less toxic, and also act in the macrophage acidic environment promoted by the infection. Objective: The aim of this study was to investigate lapachol and β-lapachone activities in combination with other drugs against Mycobacterium tuberculosis at neutral and acidic pH and its cytotoxicity. Design: Inhibitory and bactericidal activities against M. tuberculosis and clinical isolates were determined. Drug combination and cytotoxicity assay were carried out using standard TB drugs and/or N-acetylcysteine (NAC). Results: Both naphthoquinones presented activity against MDR clinical isolates. The combinations with the first-line TB drugs demonstrated an additive effect and β-lapachone+NAC were synergic against H₃₇Rv. Lapachol activity at acidic pH and its association with NAC improved the selectivity index. Lapachol and β-lapachone produced cell morphological changes in bacilli at pH 6.0 and 6.8, respectively. Conclusion: Lapachol revealed promising anti-TB activity, especially associated with NAC.

Milk fermented by Lactobacillus casei CRL431 administered as an immune adjuvant in models of breast cancer and metastasis under chemotherapy

Chemotherapy is the most common treatment for breast cancer and its metastasis; however, it affects the patients' quality of life. Previously, it was demonstrated that milk fermented by Lactobacillus casei CRL431 (probiotic fermented milk (PFM)) exerted benefits against breast cancer metastasis by modulating the immune response in a mouse model. The aim of this work was to evaluate PFM administration on the side effects of capecitabine and on its anti-tumour/anti-metastatic effects. In vitro, 4T1 breast cancer cells were treated with capecitabine in the presence of immune cells' conditioned media from mice administered with PFM. Cell viability was evaluated by MTT assay. In vivo, BALB/c mice (healthy, bearing breast cancer or with potential metastasis) were treated or not with capecitabine and administered with PFM. Blood cell counts, intestinal damages, lung histology and serum cytokines were evaluated. Results showed that capecitabine's toxicity on 4T1 cells was improved by the immune cells from mice that received PFM when the lower dose of capecitabine was evaluated. PFM reduced capecitabine side effects in all the mouse models and decreased intestinal mucositis and mortality. PFM administration to mice under chemotherapy maintained the anti-cancer/anti-metastasis effect of capecitabine with similar or decreased values for serum IL-10 and TNF-α and decreased IL-6, a cytokine related to poor prognosis in advanced cancer patients. In addition, PFM by itself reduced metastasis without side effects and improved the host's immune response. PFM has a potential to be administered as an immune adjuvant in patients under chemotherapy without affecting the treatment. KEY POINTS: • Milk fermented by L. casei CRL431 (PFM) diminished capecitabine side effects. • Capecitabine's toxicity on 4T1 cells was improved by the PFM-stimulated immune cells. • PFM maintained anti-cancer/anti-metastasis effect of capecitabine in mouse models. Graphical abstract.

Significance of human microbiome in breast cancer: Tale of an invisible and an invincible

The human microbiome is a mysterious treasure of the body playing endless important roles in the well-being of the host metabolism, digestion, and immunity. On the other hand, it actively participates in the development of a variety of pathological conditions including cancer. With the Human Microbiome Project initiative, metagenomics, and next-generation sequencing technologies in place, the last decade has witnessed immense explorations and investigations on the enigmatic association of breast cancer with the human microbiome. However, the connection between the human microbiome and breast cancer remains to be explored in greater detail. In fact, there are several emerging questions such as whether the host microbiota contributes to disease initiation, or is it a consequence of the disease is an irrevocably important question that demands a valid answer. Since the microbiome is an extremely complex community, gaps still remain on how this vital microbial organ plays a role in orchestrating breast cancer development. Nevertheless, undeniable evidence from studies has pinpointed the presence of specific microbial elements of the breast and gut to play a role in governing breast cancer. It is still unclear if an alteration in microbiome/dysbiosis leads to breast cancer or is it vice versa. Though specific microbial signatures have been detected to be associated with various breast cancer subtypes, the structure and composition of a core "healthy" microbiome is yet to be established. Probiotics seem to be a promising antidote for targeted prevention and treatment of breast cancer. Interestingly, these microbial communities can serve as potential biomarkers for prognosis, diagnosis, and treatment of breast cancer, thereby leading to the rise of a completely new era of personalized medicine. This review is a humble attempt to summarize the research findings on the human microbiome and its relation to breast cancer.

Anticancer Potential of Resveratrol, β-Lapachone and Their Analogues

This review aims to explore the potential of resveratrol, a polyphenol stilbene, and beta-lapachone, a naphthoquinone, as well as their derivatives, in the development of new drug candidates for cancer. A brief history of these compounds is reviewed along with their potential effects and mechanisms of action and the most recent attempts to improve their bioavailability and potency against different types of cancer.

Emerging Roles of Probiotics in Prevention and Treatment of Breast Cancer: A Comprehensive Review of Their Therapeutic Potential

Breast cancer is the most common cancer among women. Need for novel preventive and curative approaches with more safety than the present one seems inevitable. This review is devoted to potentially favorable role of probiotics in prevention and treatment of breast cancer as well as their alleviating role regarding chemotherapy-induced side effects. Literature was searched for human, animal, and in vitro studies about the role of probiotics in breast cancer. In vitro studies showed that probiotic intervention induces cancer cells apoptosis and inhibits their proliferation. In animal models, treatment with probiotics inhibited tumor growth and reduced tumor size; also, the immunomodulatory, antiangiogenesis and antimetastatic activities of probiotics were illustrated. Human studies showed that intake of Lactobacillus casei shirota reduced the breast cancer incidence and consumption of fermented milk products and yogurt was inversely associated with breast cancer incidence; however, no study regarding the curative role of probiotics in breast cancer is available. Studies on the effect of probiotics on chemotherapy-induced side effects in breast cancer were contradictory but showed potential for more investigation. Probiotics seem to have a potential role in both prevention and treatment of breast cancer. However, more clinical studies are needed to elucidate their efficacy and safety.

An Overview of Biotransformation and Toxicity of Diterpenes

Diterpenes have been identified as active compounds in several medicinal plants showing remarkable biological activities, and some isolated diterpenes are produced at commercial scale to be used as medicines, food additives, in the synthesis of fragrances, or in agriculture. There is great interest in developing methods to obtain derivatives of these compounds, and biotransformation processes are interesting tools for the structural modification of natural products with complex chemical structures. Biotransformation processes also have a crucial role in drug development and/or optimization. The understanding of the metabolic pathways for both phase I and II biotransformation of new drug candidates is mandatory for toxicity and efficacy evaluation and part of preclinical studies. This review presents an overview of biotransformation processes of diterpenes carried out by microorganisms, plant cell cultures, animal and human liver microsomes, and rats, chickens, and swine in vivo and highlights the main enzymatic reactions involved in these processes and the role of diterpenes that may be effectively exploited by other fields.

Antitumor mechanisms of bifidobacteria

Cancer remains one of the most common causes of mortality globally. Chemotherapy, one of the major treatment strategies for cancer, primarily functions by targeting the cancer cells and affecting them physiologically, but also affects normal cells, which is a major concern at present. Therefore, adverse effects of chemotherapy drugs, including myelosuppression and liver and kidney damage, are of concern. Now, microbial products have attracted attention in cancer treatment research. Notably, carcinogenesis is considered to be associated with microbial dysbiosis, particularly the positive antitumor effects of bifidobacteria. Although there remains a substantial amount to be understood about the regulation of bifidobacteria, bifidobacteria remain an attractive and novel source of cancer therapeutics. The present review focuses on introducing the latest information on the antitumor effects of bifidobacteria and to propose future strategies for using bifidobacteria in the development of cancer therapeutics.

Immunomodulatory effects and anti-Candida activity of lactobacilli in macrophages and in invertebrate model of Galleria mellonella

Due to the growing number of multi-resistant Candida spp., adjuvant treatments that may help combat these fungal pathogens are relevant and useful. This study evaluated the immunomodulation and anti-Candida activity of Lactobacillus rhamnosus (LR), Lactobacillus acidophilus and Lactobacillus paracasei suspensions, either single- or multiple-strain, in mouse macrophages (RAW 264.7) and Galleria mellonella (GM). Mouse macrophages were activated by different lactobacilli suspensions and challenged with C. albicans (CA). Tumor necrosis factor (TNF)-α, interleukin IL-1β, IL-6 and IL-17 production and cell viability were investigated. LR was the best suspension for stimulating all evaluated cytokines and thus was used in subsequent in vivo assays. Two C. albicans clinical strains, CA21 and CA60, were then added to the GM assays to further confirm the results. LR suspension was injected into the larvae 24 h before challenging with CA. Survival curve, CFU per larva and hemocytes were counted. In the GM, the LR suspension increased the survival rate and hemocyte counts and decreased the CFU per larva counts for all groups. Lactobacilli suspensions presented strain-dependent immunomodulation; however, single suspensions showed better results. Anti-Candida activity was demonstrated by decreased Candida counts in the GM with the use of LR.

Microbial Metabolism of Atovaquone and Cytotoxicity of the Produced Phase I Metabolite

BACKGROUND AND OBJECTIVES

Atovaquone is a hydroxynaphthoquinone with selective action in the mitochondrial respiratory chain of malaria parasite. It is employed for both the treatment and prevention of malaria, in a combination with proguanil. The aim of this study was to elucidate the in vitro metabolites from atovaquone and to evaluate their cytotoxic activities.

METHODS

The biotransformation of atovaquone was performed using Mucor rouxii NRRL 1894, Cunninghamella echinulata var. elegans ATCC 8688a and C. elegans ATCC 10028b, which have been reported as microbial models of mammalian drug metabolism. Experiments were also carried out with two probiotic strains from the human intestinal tract: Bifidobacterium sp. and Lactobacillus acidophilus. The phase I metabolite was isolated, its chemical structure was elucidated and its toxicity was evaluated using the neoplastic cell line SKBR-3 derived from human breast cancer and normal human fibroblast cell line GM07492-A. Cell cytotoxicity assays were also carried out with atovaquone.

RESULT

Only the fungi were able to convert atovaquone to metabolite trans-3-[4'-(4″-chlorophenyl)cyclohexyl)-1,2-dioxo-dihydro-1H-indene-3-carboxylic acid. The metabolite displayed 50 % inhibitory concentration (IC50) values of 110.20 ± 2.2 and 108.80 ± 1.5 µmol/L against breast cancer cell line SKBR-3 and fibroblasts cell line GM07492-A, respectively. The IC50 values of atovaquone were 282.30 ± 1.8 and 340.50 ± 1.4 µmol/L against breast cancer and normal fibroblasts cell lines, respectively.

CONCLUSIONS

The produced metabolite was more toxic than atovaquone and was not selective to normal or cancer cell lines. The present study is the first to report the production of atovaquone metabolite.

Antileishmanial Activity of Handroanthus serratifolius (Vahl) S. Grose (Bignoniaceae)

This study aimed to evaluate the leishmanicidal activity of ethanol extract, fractions, and isolated substance from Handroanthus serratifolius against Leishmania amazonensis. Furthermore, this activity was related to cytotoxicity, and the selectivity index was determined. The ethanol extract was obtained by maceration of the stem powder, and the extract was subjected to fractionation on chromatographic column. The lapachol was obtained by acid base extraction followed by purification in chromatographic column. The antipromastigote activity and cytotoxicity tests were carried out by the cell viability method (MTT). Modified THP-1 cells were infected with L. amazonensis promastigotes and treated for 24 h with different concentrations of the extract, fractions, and lapachol. The ethanol extract, dichloromethane, and ethyl acetate fractions were not active against promastigotes (IC₅₀ > 200 μg/mL) or cytotoxic (CC₅₀ > 500 μg/mL), and the selectivity index (SI) was greater than 2.5. The ethyl acetate fraction was active only in promastigotes; it is not cytotoxic (CC₅₀ > 500 μg/mL, SI > 5). The lapachol was selectively active only against amastigote (IS > 2.5, CC₅₀ > 500 μg/mL). In summary, lapachol and ethyl acetate fraction are promising against amastigote and promastigote forms, respectively.

Lactobacillus Casei Decreases Organophosphorus Pesticide Diazinon Cytotoxicity in Human HUVEC Cell Line

PURPOSE

Exposure to diazinon can trigger acute and chronic toxicity and significantly induces DNA damage and proapoptotic effects in different human cells. Due to the significance of probiotic bacteria antitoxin effect, this study aimed to investigate the effect of Lactobacillus casei on diazinon (DZN) cytotoxicity in human umbilical vein endothelial cells (HUVEC) in vitro.

METHODS

The cytotoxicity assessments were performed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test, DAPI (4',6-diamidino-2-phenylindole) staining and flow cytometric methodologies.

RESULTS

Cytotoxic assessments through flow cytometry/ DAPI staining demonstrated that apoptosis is the main cytotoxic mechanism of diazinon in HUVEC cells and L. casei could decrease the diazinon cytotoxic effects on toxicants.

CONCLUSION

the screen of total bacterial secreted metabolites can be considered as a wealthy source to find the new active compounds to introduce as reducing agricultural remained pesticide cytotoxicity effects on the human food chain.

Antifungal and Cytotoxic Assessment of Lapachol Derivatives Produced by Fungal Biotransformation

In the screening for biological active compounds, the biotransformation processes catalyzed by filamentous fungi are useful because they can provide information about the possible appearance of toxic metabolites after oral administration and also generate new leads. In this paper, biotransformation of lapachol (1) by three fungal strains, Mucor circinelloides NRRL3631, Botrytis cinerea UCA992 and Botrytis cinerea 2100, has been investigated for the first time. Lapachol (1) was biotransformed into avicequinone-A (2) by M. circinelloides, 3′-hydroxylapachol (3) by B. cinerea, and into dehydro-α-lapachone (4) by both fungi. All these compounds were evaluated for their cytotoxic activities. The metabolite 2 displayed non-selective cytotoxicity against tumor and normal cell lines, 3 did not show cytotoxicity against the same cells, while 4 showed higher cytotoxicity against cancer cell lines than lapachol (1). The transformation of 1 into harmless and reactive metabolites evidences the importance of the evaluation of drug metabolism in the drug discovery process. Antifungal potential of lapachol (1) and its metabolites 2 and 4 against B. cinerea has also been evaluated. Dehydro-α-lapachone (4) has been shown to be less toxic to fungal growth than lapachol (1), which indicates a detoxification mechanism of the phytopathogen.