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1.
Nat Commun ; 15(1): 583, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38233381

ABSTRACT

In contrast to rodents, the mechanisms underlying human trophectoderm and early placenta specification are understudied due to ethical barriers and the scarcity of embryos. Recent reports have shown that human pluripotent stem cells (PSCs) can differentiate into trophectoderm (TE)-like cells (TELCs) and trophoblast stem cells (TSCs), offering a valuable in vitro model to study early placenta specification. Here, we demonstrate that the VGLL1 (vestigial-like family member 1), which is highly expressed during human and non-human primate TE specification in vivo but is negligibly expressed in mouse, is a critical regulator of cell fate determination and self-renewal in human TELCs and TSCs derived from naïve PSCs. Mechanistically, VGLL1 partners with the transcription factor TEAD4 (TEA domain transcription factor 4) to regulate chromatin accessibility at target gene loci through histone acetylation and acts in cooperation with GATA3 and TFAP2C. Our work is relevant to understand primate early embryogenesis and how it differs from other mammalian species.


Subject(s)
Pluripotent Stem Cells , Transcription Factors , Pregnancy , Female , Humans , Mice , Animals , Cell Lineage/genetics , Transcription Factors/genetics , Trophoblasts/physiology , Cell Differentiation/genetics , Mammals , Primates , DNA-Binding Proteins/genetics , TEA Domain Transcription Factors
2.
Cell ; 186(23): 4996-5014.e24, 2023 11 09.
Article in English | MEDLINE | ID: mdl-37949056

ABSTRACT

A formal demonstration that mammalian pluripotent stem cells possess preimplantation embryonic cell-like (naive) pluripotency is the generation of chimeric animals through early embryo complementation with homologous cells. Whereas such naive pluripotency has been well demonstrated in rodents, poor chimerism has been achieved in other species including non-human primates due to the inability of the donor cells to match the developmental state of the host embryos. Here, we have systematically tested various culture conditions for establishing monkey naive embryonic stem cells and optimized the procedures for chimeric embryo culture. This approach generated an aborted fetus and a live chimeric monkey with high donor cell contribution. A stringent characterization pipeline demonstrated that donor cells efficiently (up to 90%) incorporated into various tissues (including the gonads and placenta) of the chimeric monkeys. Our results have major implications for the study of primate naive pluripotency and genetic engineering of non-human primates.


Subject(s)
Embryonic Stem Cells , Genetic Engineering , Haplorhini , Animals , Female , Pregnancy , Haplorhini/genetics , Live Birth , Mammals , Pluripotent Stem Cells , Primates , Genetic Engineering/methods
3.
Cell Stem Cell ; 30(9): 1235-1245.e6, 2023 09 07.
Article in English | MEDLINE | ID: mdl-37683604

ABSTRACT

Heterologous organ transplantation is an effective way of replacing organ function but is limited by severe organ shortage. Although generating human organs in other large mammals through embryo complementation would be a groundbreaking solution, it faces many challenges, especially the poor integration of human cells into the recipient tissues. To produce human cells with superior intra-niche competitiveness, we combined optimized pluripotent stem cell culture conditions with the inducible overexpression of two pro-survival genes (MYCN and BCL2). The resulting cells had substantially enhanced viability in the xeno-environment of interspecies chimeric blastocyst and successfully formed organized human-pig chimeric middle-stage kidney (mesonephros) structures up to embryonic day 28 inside nephric-defective pig embryos lacking SIX1 and SALL1. Our findings demonstrate proof of principle of the possibility of generating a humanized primordial organ in organogenesis-disabled pigs, opening an exciting avenue for regenerative medicine and an artificial window for studying human kidney development.


Subject(s)
Induced Pluripotent Stem Cells , Pluripotent Stem Cells , Humans , Swine , Animals , Mesonephros , Embryo, Mammalian , Blastocyst , Mammals , Homeodomain Proteins
4.
Asian Pac J Cancer Prev ; 24(7): 2361-2368, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37505767

ABSTRACT

BACKGROUND: E-cadherin (CDH1), a tumor suppressor gene, encodes a transmembrane glycoprotein that helps in maintaining squamous epithelium integrity of the cervix. We aimed to investigate the association between -160C/A genetic polymorphism in CDH1 and the risk of cervical cancer in Bangladeshi females. METHOD: The present case-control study included 117 cervical cancer cases and 147 age-matched controls. The genomic DNA was extracted from peripheral blood and genotyped by using PCR-RFLP analysis. RESULTS: Genotyping results demonstrated that the occurrences of normal homozygous (-160C/C), heterozygous (-160C/A) and variant homozygous (-160A/A) genotypes were 64.10, 27.35 and 8.55% in cases, and 77.55, 19.73 and 2.72% in controls, respectively. Compared to normal C/C genotype, variant A/A and combined (C/A+A/A) or 'any A' genotypes exhibited 3.80-fold (95% CI=1.150-12.561, P=0.029) and 1.93-fold (95% CI=1.126-3.323, P=0.017) increased risk of cervical cancer development. The -160C allele was found to be positively linked to cervical cancer incidence and raised the risk by 1.81-fold (OR= 1.814, 95% CI=1.152-2.857, p=0.01). Moreover, women carrying -160A/A variant homozygosity along with an early marital history (<18 years) were more susceptible to cervical cancer development (χ2 =6.605, p=0.037). CONCLUSION: The study suggests that the (A/A) and combined (C/A +A/A) genotypes are associated with greater risk of cervical cancer in Bangladeshi women.


Subject(s)
Antigens, CD , Cadherins , Genetic Predisposition to Disease , Uterine Cervical Neoplasms , Female , Humans , Antigens, CD/genetics , Cadherins/genetics , Case-Control Studies , Cervix Uteri , Genotype , Polymorphism, Single Nucleotide , Uterine Cervical Neoplasms/epidemiology , Uterine Cervical Neoplasms/genetics
5.
Cell Stem Cell ; 30(4): 362-377.e7, 2023 04 06.
Article in English | MEDLINE | ID: mdl-37028403

ABSTRACT

Human stem cell-derived blastoids display similar morphology and cell lineages to normal blastocysts. However, the ability to investigate their developmental potential is limited. Here, we construct cynomolgus monkey blastoids resembling blastocysts in morphology and transcriptomics using naive ESCs. These blastoids develop to embryonic disk with the structures of yolk sac, chorionic cavity, amnion cavity, primitive streak, and connecting stalk along the rostral-caudal axis through prolonged in vitro culture (IVC). Primordial germ cells, gastrulating cells, visceral endoderm/yolk sac endoderm, three germ layers, and hemato-endothelial progenitors in IVC cynomolgus monkey blastoids were observed by single-cell transcriptomics or immunostaining. Moreover, transferring cynomolgus monkey blastoids to surrogates achieves pregnancies, as indicated by progesterone levels and presence of early gestation sacs. Our results reveal the capacity of in vitro gastrulation and in vivo early pregnancy of cynomolgus monkey blastoids, providing a useful system to dissect primate embryonic development without the same ethical concerns and access challenges in human embryo study.


Subject(s)
Embryo, Mammalian , Gastrulation , Pregnancy , Animals , Female , Humans , Macaca fascicularis , Germ Layers , Embryonic Development , Endoderm , Cell Differentiation
6.
Nature ; 605(7909): 315-324, 2022 05.
Article in English | MEDLINE | ID: mdl-35314832

ABSTRACT

After fertilization, the quiescent zygote experiences a burst of genome activation that initiates a short-lived totipotent state. Understanding the process of totipotency in human cells would have broad applications. However, in contrast to in mice1,2, demonstration of the time of zygotic genome activation or the eight-cell (8C) stage in in vitro cultured human cells has not yet been reported, and the study of embryos is limited by ethical and practical considerations. Here we describe a transgene-free, rapid and controllable method for producing 8C-like cells (8CLCs) from human pluripotent stem cells. Single-cell analysis identified key molecular events and gene networks associated with this conversion. Loss-of-function experiments identified fundamental roles for DPPA3, a master regulator of DNA methylation in oocytes3, and TPRX1, a eutherian totipotent cell homeobox (ETCHbox) family transcription factor that is absent in mice4. DPPA3 induces DNA demethylation throughout the 8CLC conversion process, whereas TPRX1 is a key executor of 8CLC gene networks. We further demonstrate that 8CLCs can produce embryonic and extraembryonic lineages in vitro or in vivo in the form of blastoids5 and complex teratomas. Our approach provides a resource to uncover the molecular process of early human embryogenesis.


Subject(s)
Embryo, Mammalian , Embryonic Development , Pluripotent Stem Cells , Zygote , Humans , Chromosomal Proteins, Non-Histone/genetics , Embryo, Mammalian/cytology , Homeodomain Proteins/genetics , Pluripotent Stem Cells/cytology , Transcription Factors/genetics , Zygote/cytology
7.
Molecules ; 27(1)2022 Jan 04.
Article in English | MEDLINE | ID: mdl-35011527

ABSTRACT

Endophytic fungi are microorganisms that exist almost ubiquitously inside the various tissues of living plants where they act as an important reservoir of diverse bioactive compounds. Recently, endophytic fungi have drawn tremendous attention from researchers; their isolation, culture, purification, and characterization have revealed the presence of around 200 important and diverse compounds including anticancer agents, antibiotics, antifungals, antivirals, immunosuppressants, and antimycotics. Many of these anticancer compounds, such as paclitaxel, camptothecin, vinblastine, vincristine, podophyllotoxin, and their derivatives, are currently being used clinically for the treatment of various cancers (e.g., ovarian, breast, prostate, lung cancers, and leukemias). By increasing the yield of specific compounds with genetic engineering and other biotechnologies, endophytic fungi could be a promising, prolific source of anticancer drugs. In the future, compounds derived from endophytic fungi could increase treatment availability and cost effectiveness. This comprehensive review includes the putative anticancer compounds from plant-derived endophytic fungi discovered from 1990 to 2020 with their source endophytic fungi and host plants as well as their antitumor activity against various cell lines.


Subject(s)
Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Biological Products/chemistry , Biological Products/pharmacology , Endophytes/chemistry , Fungi/chemistry , Animals , Antineoplastic Agents/isolation & purification , Biological Products/isolation & purification , Clinical Studies as Topic , Drug Discovery/methods , Drug Evaluation, Preclinical , Endophytes/metabolism , Fungi/metabolism , Humans , Plants/microbiology , Structure-Activity Relationship
8.
Saudi J Biol Sci ; 28(7): 3893-3900, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34220245

ABSTRACT

Tinosporide and 8-hydroxytinosporide isolated from Tinospora cordifolia were evaluated for acetylcholinesterase (AChE) and butylcholinesterase (BuChE) inhibitory activities. The structure of the compound was confirmed by spectroscopic analysis, whereas cholinesterase inhibition was investigated by Ellman method using donepezil as standard drug and the data were presented as IC50 (µg/ml ± SEM). Furthermore, donepezil, tinosporide and 8-hydroxytinosporide were executed for docking analysis. The results from the isolated compounds TC-16R confirmed as tinosporide promisingly inhibited AChE with IC50 value of 13.45 ± 0.144, whereas TC-19R confirmed as 8-hydroxytinosporide moderately inhibited AChE with IC50 value of 46.71 ± 0.511. In case of BuChE inhibition, the IC50 values were found to be 408.50 ± 17.197 and 317.26 ± 6.918 for tinosporide and 8-hydroxytinosporide, respectively. The in silico studies revealed that the ligand tinosporide fit with the binding sites and inhibited AChE. Overall, the study findings suggested that tinosporide would be a complementary noble molecule of donepezil which is correlated with its pharmacological activity through in vitro studies, while 8-hydroxytinosporide modestly inhibited BuChE and the results are very close to the standard donepezil.

9.
Breast Cancer Res Treat ; 182(3): 739-750, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32562117

ABSTRACT

BACKGROUND: Genetic polymorphisms in DNA repair genes, XRCC1 (Arg399Gln) and XRCC3 (Thr241Met), may affect their DNA repair capacity leading to individual variation in breast cancer susceptibility among Bangladeshi females. METHODS: The case-control study comprised 121 breast cancer patients and 133 healthy controls. Genomic DNA isolated from peripheral blood was genotyped for target SNPs using PCR-RFLP method. RESULTS: For XRCC1, heterozygous Arg/Gln and homozygous Gln/Gln genotypes showed 1.78-fold (95% CI 1.0084 to 3.1442, p = 0.0467) and 2.41-fold (95% CI 1.0354 to 5.5914, p = 0.0413) increased risk of breast cancer, respectively, when compared with Arg/Arg genotype. The presence of any XRCC1 Gln showed association with 1.93-fold increased risk. The variant Gln allele was associated with increased risk of breast cancer (95% CI 1.1885 to 2.6805, p = 0.0052). For XRCC3, Thr/Met heterozygous and combined Thr/Met + Met/Met genotypes were associated with 1.85-fold (95% CI 1.0815 to 3.1834, p = 0.0248) and 1.89-fold (95% CI 1.1199 to 3.1908, p = 0.0171) higher risk, respectively, compared to Thr/Thr genotypes. The variant Met allele showed significant association with increased breast cancer susceptibility. Among cases genotype frequencies were significantly different in patients with age 55 or above, and with menopause and diabetes. CONCLUSION: XRCC1 (Arg399Gln) and XRCC3 (Thr241Met) polymorphisms may be associated with increased breast cancer risk in Bangladeshi females.


Subject(s)
Breast Neoplasms/genetics , DNA Repair , DNA-Binding Proteins/genetics , X-ray Repair Cross Complementing Protein 1/genetics , Adolescent , Adult , Aged , Bangladesh/epidemiology , Biomarkers, Tumor/genetics , Breast Neoplasms/epidemiology , Breast Neoplasms/pathology , Case-Control Studies , Female , Follow-Up Studies , Genetic Predisposition to Disease , Genotype , Humans , Middle Aged , Polymorphism, Single Nucleotide , Prognosis , Risk Factors , Young Adult
10.
Tumour Biol ; 41(3): 1010428319830837, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30880589

ABSTRACT

The polymorphisms of invasion suppressor gene CDH1 and DNA mismatch repair gene Exo1 have been reported to play critical role in the development, tumorigenesis, and progression of several kinds of cancers including prostate cancer. This study was designed to analyze the contribution of single-nucleotide polymorphisms of the CDH1 (-160C/A) and Exo1 (K589E) to prostate cancer susceptibility in Bangladeshi population. The study included 100 prostate cancer cases and age-matched 100 healthy controls. Polymerase chain reaction-restriction fragment length polymorphism analysis was used to determine the genetic polymorphisms. A significant association was found between CDH1 -160C/A (rs16260) and Exo1 (rs1047840, K589E) polymorphisms and prostate cancer risk. In case of CDH1 -160C/A polymorphism, the frequencies of the three genotypes C/C,C/A, and A/A were 45%, 48%, and 7% in cases and 63%, 32%, and 5% in controls, respectively. The heterozygote C/A genotype and combined C/A + A/A genotypes showed 2.10-fold (odds ratio = 2.1000, 95% confidence interval = 1.2956-4.0905, p = 0.013) and 2.08-fold (odds ratio = 2.0811, 95% confidence interval = 1.1820-3.6641, p = 0.011) increased risk of prostate cancer, respectively, when compared with homozygous C/C genotypes. The variant A allele also was associated with increased risk of prostate cancer (odds ratio = 1.6901, 95% confidence interval = 1.0740-2.6597, p = 0.0233). In case of Exo1 (K589E) polymorphism, G/A heterozygote, A/A homozygote, and combined G/A + A/A genotypes were found to be associated with 2.30-, 4.85-, and 3.04-fold higher risk of prostate cancer, respectively (odds ratio = 2.3021, 95% confidence interval = 2.956-4.0905, p = 0.0031; odds ratio = 4.8462, 95% confidence interval = 1.0198-23.0284, p = 0.0291; OR = 3.0362, 95% confidence interval = 1.7054-5.4053, p = 0.0001, respectively). The "A" allele showed significant association with increased susceptibility (2.29-fold) to prostate cancer (odds ratio = 2.2955, 95% confidence interval = 1.4529-3.6270, p = 0.0004). Our results suggest that CDH1 -160C/A and Exo1 K589E polymorphisms are associated with increased susceptibility to prostate cancer in Bangladeshi population.


Subject(s)
Antigens, CD/genetics , Cadherins/genetics , DNA Repair Enzymes/genetics , Ethnicity/genetics , Exodeoxyribonucleases/genetics , Genetic Predisposition to Disease/genetics , Polymorphism, Restriction Fragment Length/genetics , Polymorphism, Single Nucleotide/genetics , Prostatic Neoplasms/genetics , Aged , Alleles , Bangladesh , Case-Control Studies , Genotype , Humans , Male , Middle Aged
11.
Toxicol Rep ; 3: 861-865, 2016.
Article in English | MEDLINE | ID: mdl-28959613

ABSTRACT

OBJECTIVE: Endophytes have the potential to synthesize various bioactive secondary metabolites. The aim of the study was to find new cytotoxic and antibacterial metabolites from endophytic fungus, Cladosporium sp. isolated from the leaves of Rauwolfia serpentina (L.) Benth. ex Kurz. (Fam: Apocyanaceae). MATERIALS AND METHODS: The endophytic fungus was grown on potato dextrose agar medium and extracted using ethyl acetate. Secondary metabolites were isolated by chromatographic separation and re-crystallization, and structures were confirmed by 1H NMR, 13C NMR and mass spectroscopic data. The cytotoxicity was determined by WST-1 assay and brine shrimp lethality bioassay, while antibacterial activity was assessed by disc diffusion method. RESULTS: Two naphthoquinones, namely anhydrofusarubin (1) and methyl ether of fusarubin (2), were isolated from Cladosporium sp. The isolated compounds 1 and 2, by WST-1 assay against human leukemia cells (K-562) showed potential cytotoxicity with IC50 values of 3.97 µg/mL and 3.58 µg/mL, respectively. Initial screening of crude ethyl acetate extract and column fractions F-8 and F-10 exhibited noticeable cytotoxicity to brine shimp nauplii with LC50 values of 42.8, 1.2 and 2.1 µg/mL, respectively. Moreover, the isolated compound 2 (40 µg/disc) showed prominent activities against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Bacillus megaterium with an average zone of inhibition of 27 mm, 25 mm, 24 mm and 22 mm, respectively and the activities were compared with kanamycin (30 µg/disc). CONCLUSION: Our findings indicate that anhydrofusarubin (1) and methyl ether of fusarubin (2) might be useful lead compounds to develop potential cytotoxic and antimicrobial drugs.

12.
Adv Pharm Bull ; 4(4): 379-83, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25436195

ABSTRACT

PURPOSE: The aim of this study was to characterize the binding profile as well as to notify the interaction of palmitic acid with metoprolol succinate at its binding site on albumin. METHODS: The binding of metoprolol succinate to bovine serum albumin (BSA) was studied by equilibrium dialysis method (ED) at 27°C and pH 7.4, in order to have an insight in the binding chemistry of the drug to BSA in presence and absence of palmitic acid. The study was carried out using ranitidine as site-1 and diazepam as site-2 specific probe. RESULTS: Different analysis of binding of metoprolol succinate to bovine serum albumin suggested two sets of association constants: high affinity association constant (k1 = 11.0 x 10(5) M(-1)) with low capacity (n1 = 2) and low affinity association (k2 = 4.0×10(5) M(-1)) constant with high capacity (n2 = 8) at pH 7.4 and 27°C. During concurrent administration of palmitic acid and metoprolol succinate in presence or absence of ranitidine or diazepam, it was found that palmitic acid displaced metoprolol succinate from its binding site on BSA resulting reduced binding of metoprolol succinate to BSA. The increment in free fraction of metoprolol succinate was from 26.27% to 55.08% upon the addition of increased concentration of palmitic acid at a concentration of 0×10(-5) M to 16×10(-5) M. In presence of ranitidine and diazepam, palmitic acid further increases the free fraction of metoprolol succinate from 33.05% to 66.95% and 40.68% to 72.88%, respectively. CONCLUSION: This data provided the evidence of interaction at higher concentration of palmitic acid at the binding sites on BSA, which might change the pharmacokinetic properties of metoprolol succinate.

13.
Phytother Res ; 24(7): 1084-7, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20077435

ABSTRACT

Polygonum flaccidum Meissn. is an annual herb, native to Bangladesh, and well known for its analgesic, anti-inflammatory, diuretic, purgative and insecticidal properties, and also for its use against snake-bites. The analgesic and the diuretic properties of alpha-santalone (1), isolated from the aerial parts of Polygonum flaccidum, were assessed by the acetic-acid-induced writhing method and the Lipschitz test, respectively. Complete (1)H and (13)C NMR data of 1 are also presented.


Subject(s)
Analgesics/pharmacology , Bridged-Ring Compounds/pharmacology , Diuretics/pharmacology , Plant Extracts/pharmacology , Polygonum/chemistry , Sesquiterpenes/pharmacology , Animals , Bridged-Ring Compounds/isolation & purification , Female , Male , Mice , Plant Components, Aerial/chemistry , Sesquiterpenes/isolation & purification
14.
Prostaglandins Other Lipid Mediat ; 83(3): 219-24, 2007 May.
Article in English | MEDLINE | ID: mdl-17481559

ABSTRACT

For the determination of prostaglandin (PG) D(2) produced by cultured cells in response to external stimuli, immunological methods would be convenient and useful. However, PGD(2) is unstable under the physiological conditions, so that it has been difficult to get a specific antibody for the parent PGD(2). In an attempt to get a specific antibody for PGD(2), we tried to prepare monoclonal antibodies for 11-deoxy-11-methylene-PGD(2), a novel, chemically stable, isosteric analogue of PGD(2). We successfully cloned a hybridoma cell line secreting a monoclonal antibody reacting specifically with the parent PGD(2). To develop the enzyme-linked immunosorbent assay (ELISA) for PGD(2), the immobilized antigen using the stable PGD(2) derivative was immunoreacted in a competitive manner with the monoclonal antibody in presence of free PGD(2). The optimization of the assay provided a sensitive calibration curve for PGD(2) from 0.32 pg to 0.18 ng with a value of 7.6 pg at 50% displacement. PGD(2) was almost stable during the ELISA condition. The developed assay method was useful for applying to the direct determination of PGD(2) in the culture medium of mouse 3T3-L1 adipocytes. The incubation of PGD(2) in the maturation medium of adipocytes at 37 degrees C caused the chemical conversion into PGJ(2) derivatives. The conversion became more evident after 6 h of the incubation. These findings indicate the importance of considering the optimal time for collecting the samples to be determined for PGD(2) before the conversion starts to occur.


Subject(s)
Enzyme-Linked Immunosorbent Assay , Haptens , Prostaglandin D2/analogs & derivatives , Prostaglandin D2/analysis , 3T3-L1 Cells , Adipocytes/cytology , Adipocytes/metabolism , Animals , Antibodies, Monoclonal/metabolism , Calibration , Cell Line , Cloning, Molecular , Culture Media, Conditioned/chemistry , Drug Stability , Hybridomas/cytology , Mice , Prostaglandin D2/immunology , Sensitivity and Specificity , Temperature
15.
FEBS Lett ; 580(30): 6885-90, 2006 Dec 22.
Article in English | MEDLINE | ID: mdl-17150216

ABSTRACT

15-Deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)) has been identified as a natural ligand for peroxisome proliferator-activated receptor (PPAR) gamma to promote adipogenesis. However, it remains elusive about the ability of PPARgamma-expressing adipocytes to produce PGJ(2) series and the role in the life cycle of adipocytes. Here, we developed an enzyme-linked immunosorbent assay specific for 15d-PGJ(2). The analysis using this method revealed the increase in the endogenous synthesis of immunoreactive 15d-PGJ(2) in cultured adipocytes during the maturation phase. Further studies using cyclooxygenase inhibitors clarified the contribution of endogeous 15d-PGJ(2) produced by mature adipocytes to upregulation of fat storage in an autocrine manner.


Subject(s)
Adipocytes/cytology , Adipocytes/metabolism , Cell Differentiation , Prostaglandin D2/analogs & derivatives , Up-Regulation , Animals , Biomarkers , Cell Line , Enzyme-Linked Immunosorbent Assay , Gene Expression , Isoenzymes/genetics , Mice , Prostaglandin D2/biosynthesis , Prostaglandin-Endoperoxide Synthases/genetics , Signal Transduction
16.
Pak J Pharm Sci ; 18(3): 1-7, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16380336

ABSTRACT

Two promising antibiotics, JF-A and JF-B were isolated from the chloroform extract of a Banglaeshi Streptomyces strain. The mean zones of inhibition produced by the chloroform extract (400 microg/disc), JF-A (200 microg/disc) and JF-B (200 microg/disc) against 19 pathogenic bacteria were found to be 9-50, 12-38 and 10-41 mm while those produced by a standard antibiotic, kanamycin were 11-40 mm at 30 microg/disc. MICs of JF-A and JF-B were determined to be 64 microg/ml against Bacillus subtilis and 64 and 128 microg/ml against Shigella sonnei, respectively. The extract and the antibiotics were also tested for cytotoxicity against Artemia salina nauplii and LC50 values of 23.26, 18.05 and 32.27 microg/ml were obtained. 90% mortality of shrimp nauplii was observed at 69.18, 50.12 and 110.91 microg/ml, respectively. In a potato disc bioassay, the chloroform extract at 25 microg/disc demonstrated 37.39% inhibition of crown gall tumour induced by G -ve Agrobacterium tumefaciens B6 and the result was statistically significant (P < 0.05). The sub-acute toxicity studies on the JF-A and JF-B reflected innocuous nature of these antibiotics on hepatic, renal and haemopoietic system of rats at 1 mg/kg b.w. on daily administration for 21 consecutive days. This is also confirmed by detailed histopathological studies. No mortality was observed in experimental animals.


Subject(s)
Anti-Bacterial Agents/isolation & purification , Hematopoietic System/drug effects , Kidney/drug effects , Liver/drug effects , Animals , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/toxicity , Artemia , Bacteria/drug effects , Lethal Dose 50 , Male , Rats , Streptomyces/metabolism
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