Quorum quenching of Streptococcus mutans via the nano-quercetin-based antimicrobial photodynamic therapy as a potential target for cariogenic biofilm.

BACKGROUND: Quorum sensing (QS) system can regulate the expression of virulence factors and biofilm formation in Streptococcus mutans. Antimicrobial photodynamic therapy (aPDT) inhibits quorum quenching (QQ), and can be used to prevent microbial biofilm. We thereby aimed to evaluate the anti-biofilm potency and anti-metabolic activity of nano-quercetin (N-QCT)-mediated aPDT against S. mutans. Also, in silico evaluation of the inhibitory effect of N-QCT on the competence-stimulating peptide (CSP) of S. mutans was performed to elucidate the impact of aPDT on various QS-regulated genes. METHODS: Cytotoxicity and intracellular reactive oxygen species (ROS) generation were assessed following synthesis and confirmation of N-QCT. Subsequently, the minimum biofilm inhibitory concentration (MBIC) of N-QCT against S. mutans and anti-biofilm effects of aPDT were assessed using colorimetric assay and plate counting. Molecular modeling and docking analysis were performed to confirm the connection of QCT to CSP. The metabolic activity of S. mutans and the expression level of various genes involved in QS were evaluated by flow cytometry and reverse transcription quantitative real-time PCR, respectively. RESULTS: Successful synthesis of non-toxic N-QCT was confirmed through several characterization tests. The MBIC value of N-QCT against S. mutans was 128 µg/mL. Similar to the crystal violet staining, the results log10 CFU/mL showed a significant degradation of preformed biofilms in the group treated with aPDT compared to the control group (P < 0.05). Following aPDT, metabolic activity of S. mutans also decreased by 85.7% (1/2 × MBIC of N-QCT) and 77.3% (1/4 × MBIC of N-QCT), as compared to the control values (P < 0.05). In silico analysis showed that the QCT molecule was located in the site formed by polypeptide helices of CSP. The relative expression levels of the virulence genes were significantly decreased in the presence of N-QCT-mediated aPDT (P < 0.05). CONCLUSIONS: The combination of N-QCT with blue laser as a QQ-strategy leads to maximum ROS generation, disrupts the microbial biofilm of S. mutans, reduces metabolic activity, and downregulates the expression of genes involved in the QS pathway by targeting genes of the QS signaling system of S. mutans.

Anti-leishmanial effects of resveratrol and resveratrol nanoemulsion on Leishmania major.

BACKGROUND: Leishmaniasis is a vector-borne disease that is endemic in the tropical and sub-tropical areas of the world. Low efficacy and high cytotoxicity of the current treatment regimens for leishmaniasis is one of the most important health problems. In this experimental study, anti-leishmanial effects of different concentrations of resveratrol and resveratrol nano-emulsion (RNE) were assessed. METHODS: RNE was prepared using the probe ultra-sonication method. The cytotoxicity was evaluated using the MTT technique on the L929 cell line. The anti-leishmanial activities on promastigotes of leishmania were assessed using vital staining and infected BALB/c mice were used to assess the in vivo anti-leishmanial effects. RESULTS: In vitro and in vivo assays revealed that all concentrations of resveratrol and RNE had valuable inhibitory effects against Leishmania major in comparison to the control group (P < 0.05). The half maximal inhibitory concentration (IC50) values were calculated as 16.23 and 35.71 µg/mL for resveratrol and RNE, respectively. Resveratrol and RNE showed no cytotoxicity against the L929 cell line. CONCLUSIONS: According to the potent in vitro and in vivo anti-leishmanial activity of RNE at low concentration against L. major, we suggest that it could be a promising anti-leishmanial therapeutic against L. major in the future.

Actin Gene-Based Molecular Typing of Trichomonas vaginalis Clinical Isolates from the North of Iran.

AIM: The aim of the current study is to evaluate the prevalence of trichomoniasis in men and women in the north of Iran and to find genotypes in the positive clinical specimens based on T. vaginalis actin gene. MATERIALS AND METHODS: Women's genital (n = 500) and men's urine (n = 1500) samples were collected from the participants referred to clinics in Mazandaran Province, northern Iran, during 2006-2018. In addition, 1500 Pap smear specimens, archived in the Bu Ali Hospital, Sari City, Mazandaran Province, northern Iran, were examined. The specimens were examined based on parasitological methods, nested polymerase chain reaction (PCR), PCR-restriction fragment length polymorphism, and phylogenetic analysis. RESULTS: Overall, 17 (0.48%) of 3500 specimens were positive by PCR. Total prevalence was 0.55% (n = 2000) for women, of which 500 (1.4%; n = 7) specimens were collected freshly, and 1500 (0.26%; n = 4) were Pap smears. Moreover, six (0.4%) out of 1500 men urine specimens were positive. Overall, genotypes G, E, and I were detected with the prevalence of seven (0.2%), seven (0.2%), and three (0.08%), respectively. There was no significant statistical difference among the prevalence of the detected genotypes (P > 0.05). CONCLUSION: As a whole, the prevalence of trichomoniasis was low in the studied area in the north of Iran and, most importantly, the genotypes of E, G, and I were distributed among men and women in the province.

Effects of some natural products from fungal and herbal sources on Giardia lamblia in vivo.

Giardia lamblia (G. lamblia) is the most widely known protozoan parasite that causes human gastrointestinal infection worldwide. Some natural compounds exhibited pivotal effects against different infectious diseases. In this research, the antigiardial activity and cytotoxicity of fungal chitosan, nano-chitosan, Rhamnus cathartica (R. cathartica) and emodin were evaluated in Balb/c mice. Genotyping of G. lamblia was assessed by PCR-RFLP technique. Different concentrations of mentioned compounds were used to check their antigiardial and cytotoxicity effects on human intestinal epithelial cells (HT-29) after 24, 48 and 72 h. The G. lamblia strain used in the current work was genotyped and revealed as an AII assemblage. All the concentration showed acceptable activity against G. lamblia cysts and trophozoites in comparison to the negative and positive controls (furazolidone and metronidazole) in vitro (P 0.05). The maximum mortality rate (100%) was achieved at 100 and 50 µg kg-1 concentrations after 48 and 72 h of exposure time, respectively. Our results provide significant information about the new antigiardial agent and proposed the nano-chitosan and emodin for the development of new drugs against G. lamblia in the future.

Evaluation of Anticancer Activity of Camellia Sinensis in the Caco-2 Colorectal Cancer Cell Line

Background: Colorectal cancer (CRC) is widespread across the world. While conventional anticancer treatments can help the affected patients, cells of vital organs such as the kidney, lungs, bladder and nervous system may suffer from side effects of chemotherapeutic drugs, so that it is necessary to search for alternatives. From ancient times, attention has focused on medicinal plants and natural products. In the current work, Camellia sinensis, whose leaves are used to produce green tea was evaluated for anticancer effects in cell culture. Materials and Methods: A hydroalcoholic extract of Camellia sinensis young leaves was prepared by percolation and compared with Cisplatin as a known anticancer drug for effects on two cell lines: Caco-2, colon carcinoma cells, and mouse normal fibroblasts (L929). Cytotoxicity of 50, 100, 200, 400 and 800 µg/ml of Camellia sinensis extract was evaluated by MTT assay and aquaporin 5 (AQP5), detected as a biomarker for surviving cells using immunofluorescence microscopy. Results: MTT assays with hydroalcoholic extract of Camellia sinensis showed considerable inhibition of growth of Caco-2 cells, significant at 800 µg/ml (P<0.05), with little effect on L929 cells. Levels of aquaporin 5 protein decreased in Caco-2 cell culture following green tea extract treatment. Conclusion: According to the results of the current study, Camellia sinensis is a medicinal plant with potent anticancer influence which might be specific.

Human Cystic Echinococcosis in Different Geographical Zones of Iran: An Observational Study during 1995-2014.

BACKGROUND: Cystic Echinococcosis (CE) is a serious zoonotic parasitic disease in Iran. This study aimed to show the trend of the confirmed disease from 1995 to 2014 and to describe some of epidemiological aspects of the disease in Iran. METHODS: This retrospective study has been designed based on data collected from 8518 cases of CE among various geographical locations of Iran. RESULTS: The average annual number of human cases of CE was 274.8. Among 31 provinces of Iran, Razavi Khorasan from northeast part of Iran was the highest human CE infected province with the 1801 cases and Hormozgan Province in south part of the country showed the lowest the disease with the only one case of CE in 2009. Liver and lungs with the infection rate of 61% and 20%, respectively are the most infected organs, 53% of patients had one cyst in the bodies and the number of cysts in 8% of cases was more than 3 cysts. Altogether, 41% of CE cases were treated by surgery, 11% with chemotherapy and 48 % with mixed surgery and chemotherapy. CONCLUSION: Human CE is a major health problem in Iran and it is necessary to establish basic control programs. It is crucial to setting up standard diagnostic methods for early diagnosis, effective treatment, plan educational schedule for different social levels and control the disease in both definitive and intermediate hosts.

Serological evidence of human cystic echinococcosis and associated risk factors among general population in Mazandaran Province, northern Iran.

The aim of the present study was to determine the seroprevalence of CE among human referring to Health Centers in Mazandaran Province, northern Iran and to identify the risk factors involved in spreading the disease. Between 2013 and 2014, the serum samples were taken randomly from 600 subjects referring to health centers in Mazandaran Province. After obtaining informed consent for each participant, a questionnaire including demographic characteristics and associated risk factors was filled for each individual. Anti-CE antibody was tested by enzyme-linked immunosorbent assay (ELISA), using native antigen B. Our results showed 31.6% (n = 190) seropositivity. There were significant difference between seropositivity and sex and residence. Males were significantly more seropositive than females (24.6% versus 7%, P = 0.0001). Regression analysis showed that the subjects who are living in rural areas were 4.4 times more likely to be at risk to CE than urban areas (OR = 4.4; 95% CI = 2.91, 6.64). Contact with dogs, soil and consumed raw vegetables was appeared as main risk factors for CE among community in Mazandaran and it may increase the probability of infection. The high prevalence of CE among individuals indicated that hydatidosis is still a major health problem among community in the investigated areas.

The anti-giardial effectiveness of fungal and commercial chitosan against Giardia intestinalis cysts in vitro.

Chitosan with poly-N-acetylglucosamine sequences is a deacetylated derivative of chitin that can be found in the exoskeletons of crabs, shrimp and lobsters, the cuticles of insects and the cell walls of fungi. The aim of the present study was to compare the effects of fungal chitosan (FC) prepared from the cell walls of Penicillium viridicatum and Penicillium aurantiogriseum with commercially available chitosan (CC) against Giardia intestinalis cysts in vitro. The giardia cysts were isolated using a sucrose method. Four concentrations (50, 100, 200 and 400 µg/ml) of each type of prepared chitosan were applied for 10, 30, 60 and 180 min. The viability of the cysts was checked via 0.1 % eosin staining. Our results indicate that P. viridicatum (with a 47.5 % DD) and P. aurantiogriseum (with a 47.3 % DD) at different concentrations after 180 min precipitated, respectively, 56, 69, 81 and 100 %, and 63, 75, 86 and 100 % mortality rates. CC (with a 54 % DD) showed 79, 84, 93 and 100 % mortality rates. In conclusion, both FC and CC at 400 µg/ml concentrations after 180 min of exposure showed the most potent effect against G. intestinalis cysts. Accordingly, chitosan could be suggested as a new natural nanoform agent for future research in the safe and effective treatment of Giardia infections.

Survey on efficacy of chloroformic extract of Artemisia annua against Giardia lamblia trophozoite and cyst in vitro.

Giardiasis is a parasitic cosmopolitan disease that the rate of infection in developing countries is considerable. This infection directly is associated with poor hygienic conditions, poor water quality control, and overcrowding. Reinfection and drug resistance are two major problems in endemic areas. Recently, researchers are concentrating on herbal drugs as a proper solution. Therefore, the objective of the present study was to survey on efficacy of chloroformic extract of Artemisia annua against Giardia lamblia trophozoite and cyst in vitro. G. lamblia cysts were prepared from faces of giardiasis patients from different hospitals of Mazandaran Medical University. Four concentrations (1, 10, 50 and 100 mg/ml) of chloroformic extract of A. annua were utilized for 1, 5, 30, 60 and 180 min. Viability of G. lamblia cysts was confirmed by 0.1 % Eosin staining. Cyst and trophozoite contact (intermix) of G. lamblia with extract of A. annua with variant concentrations (1, 10, 50 and 100 mg/ml) after 1 and 180 min caused following cyst and trophozoite elimination rates: (67, 69, 71 and 73 %), (65, 67, 67 and 72 %), (94, 96, 97 and 99 %) and (100, 100, 100 and 100 %), respectively. Authors from the current investigation draw a conclusion that chloroformic extract of A. annua has the ability to eliminate G. lamblia cysts and trophozoites in vitro.

Scolicidal activity of biosynthesized silver nanoparticles against Echinococcus granulosus protoscolices.

Cystic hydatid disease (CHD), a helminth infection with various clinical complications caused by the larval stage of the dog tapeworm Echinococcus granulosus is considered as a public health problem in different regions of the world. To date, scolicidal agents have been broadly applied for inactivation of the fertile cysts and these scolicidal agents have several side effects on patients. Therefore, the objective of this study was to evaluate the scolicidal efficacies of synthesized silver nanoparticles (AgNPs) derived from the aqueous aerial extract of Penicillium aculeatum against protoscolices of CHD in-vitro. Protoscolices were aseptically aspirated from infected livers of sheep with CHD. Various concentrations (0.025, 0.05, 0.1 and 0.15 mg/mL) of green synthesis of Ag-NPs and different exposure times (10, 30, 60 and 120 min) were used against protoscolices of CHD. Viability of protoscolices was confirmed by 0.1% eosin staining. The findings showed that the Ag-NPs at all concentrations have high scolicidal effects. The concentrations 0.1 and 0.15 mg/mL after 120 min of exposure times showed 83% and 90% mortality rate, respectively. The least scolicidal activity of biosynthesized Ag-NPs was 40% (0.025 mg/mL and 10 min). The current investigation indicated that applying biogenic Ag-NPs may be considered as a potential scolicidal agent for CHD surgery due to being economical, safer and non-toxic compared to the used chemical materials. However, further studies are required to evaluate the efficacy of Ag-NPs in vivo.

In vitro protoscolicidal effects of fungal chitosan isolated from Penicillium waksmanii and Penicillium citrinum.

Hydatidosis is caused by a tapeworm which infects humans by the larval stage. In humans, the disease is so serious that it requires surgery for treatment. Documents show that there have been many efforts in finding new scolicidal agents for reducing the rate of the infection. The objective of this study was determination of the scolicidal effect of two fungal chitosan types, produced from Penicillium spp. and commercially chitosan (CC) on Echinococcus granulosus protoscolex. Protoscolices were aseptically aspirated from sheep livers hydatid cysts. Four concentrations (50, 100, 200, 400 µg/ml) of each type of prepared chitosan were used for 10, 30, 60 and 180 min. Viability of protoscolices was detected by 0.1 % eosin staining. Fungal chitosan which was the most bioactive type with higher degree of deacetylation showed stronger scolicidal activity in vitro (P < 0.05). Fungal chitosan could be recommended, as good as CC for hydatid cysts control and is a noble alternative for synthetic and chemical scolicidal.

In vitro treatments of Echinococcus granulosus with fungal chitosan, as a novel biomolecule.

OBJECTIVE: To determined the antiparasitic activity of the isolated chitosan from Penicillium viridicatum, Penicillium aurantiogriseum and commercial chitosan against protoscolicidal of hydatid cysts were determined. METHODS: After isolating chitosan from fungal cell walls, four concentrations (50, 100, 200, 400 µg/mL) of each type of prepared chitosan and commercial chitosan were used for 10, 30, 60, and 180 min, respectively. RESULTS: Among different type of chitosan, commercial chitosan with the highest degree of deacetylation showed high scolicidal activity in vitro. Fungal chitosan could be recommended, as good as commercial chitosan, for hydatic cysts control. CONCLUSIONS: It seems to be a good alternative to synthetic and chemical scolicidal.