Synthetic Biology towards Improved Flavonoid Pharmacokinetics

Flavonoids are a structurally diverse class of natural products that have been found to have a range of beneficial activities in humans. However, the clinical utilisation of these molecules has been limited due to their low solubility, chemical stability, bioavailability and extensive intestinal metabolism in vivo. Recently, the view has been formed that site-specific modification of flavonoids by methylation and/or glycosylation, processes that occur in plants endogenously, can be used to improve and adapt their biophysical and pharmacokinetic properties. The traditional source of flavonoids and their modified forms is from plants and is limited due to the low amounts present in biomass, intrinsic to the nature of secondary metabolite biosynthesis. Access to greater amounts of flavonoids, and understanding of the impact of modifications, requires a rethink in terms of production, more specifically towards the adoption of plant biosynthetic pathways into ex planta synthesis approaches. Advances in synthetic biology and metabolic engineering, aided by protein engineering and machine learning methods, offer attractive and exciting avenues for ex planta flavonoid synthesis. This review seeks to explore the applications of synthetic biology towards the ex planta biosynthesis of flavonoids, and how the natural plant methylation and glycosylation pathways can be harnessed to produce modified flavonoids with more favourable biophysical and pharmacokinetic properties for clinical use. It is envisaged that the development of viable alternative production systems for the synthesis of flavonoids and their methylated and glycosylated forms will help facilitate their greater clinical application.

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The Impact of Dosing Interval in a Novel Tandem Oral Dosing Strategy: Enhancing the Exposure of Low Solubility Drug Candidates in a Preclinical Setting

Journal of Drug Delivery ◽

10.1155/2011/528284 ◽

2011 ◽

Vol 2011 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Po-Chang Chiang ◽

Sarah A. South ◽

Steve P. Wene

Keyword(s):

Resource Constraints ◽

Drug Candidate ◽

Time Interval ◽

Drug Candidates ◽

Safety Studies ◽

Early Decision ◽

Dosing Strategy ◽

The Impact ◽

Low Solubility

In drug discovery, time and resource constraints necessitate increasingly early decision making to accelerate or stop preclinical programs. Early discovery drug candidates may be potent inhibitors of new targets, but all too often exhibit poor pharmaceutical or pharmacokinetic properties that limit the in vivo exposure. Low solubility of a drug candidate often leads to poor oral bioavailability and poor dose linearity. This issue is more significant for efficacy and target safety studies where high drug exposures are desired. When solubility issues are confronted, enabling formulations are often required to improve the exposure. However, this approach often requires a substantial and lengthy investment to develop the formulation. Previously, we introduced a gastrointestinal (GI) transit time-based novel oral tandem dosing strategy that enhanced in vivo exposures in rats. In this study, a refined time interval versus dose theory was tested. The resulting in vivo exposures based on altering frequency and doses were compared, and significant impacts were found.

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Methane Emissions and the Use of Desmanthus in Beef Cattle Production in Northern Australia

Animals ◽

10.3390/ani9080542 ◽

2019 ◽

Vol 9 (8) ◽

pp. 542 ◽

Cited By ~ 3

Author(s):

Bénédicte Suybeng ◽

Edward Charmley ◽

Christopher P. Gardiner ◽

Bunmi S. Malau-Aduli ◽

Aduli E. O. Malau-Aduli

Keyword(s):

Beef Cattle ◽

Agricultural Sector ◽

Production Systems ◽

Methane Emissions ◽

In Vivo Studies ◽

Northern Australia ◽

Cattle Production ◽

Beef Cattle Production ◽

The Impact

The Australian beef industry is a major contributor to the economy with an estimated annual revenue generation of over seven billion dollars. The tropical state of Queensland accounted for 48% of Australian beef and veal production in 2018. As the third biggest beef exporter in the world, Australia supplies 3% of the world’s beef exports and its agricultural sector accounts for an estimated 13.2% of its total greenhouse gas emissions. About 71% of total agricultural emissions are in the form of methane and nitrous oxide. In this review, an overview of the carbon footprint of the beef cattle production system in northern Australia is presented, with emphasis on the mitigation of greenhouse gases. The review also focuses on the tropical legume, Desmanthus, one of the more promising nutritional supplements for methane abatement and improvement of animal growth performance. Among the review’s findings is the need to select environmentally well-adapted and vigorous tropical legumes containing tannins that can persistently survive under the harsh northern Australian conditions for driving animal performance, improving meat quality and reducing methane emissions. The paper argues that the use of appropriate legumes such as Desmanthus, is a natural and preferred alternative to the use of chemicals for the abatement of methane emanating from tropical beef cattle production systems. It also highlights current gaps in knowledge and new research opportunities for in vivo studies on the impact of Desmanthus on methane emissions of supplemented tropical beef cattle.

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Decorating sdAbs with Chelators: Effect of Conjugation on Biodistribution and Functionality

Pharmaceuticals ◽

10.3390/ph14050407 ◽

2021 ◽

Vol 14 (5) ◽

pp. 407

Author(s):

Henri Baudhuin ◽

Janik Puttemans ◽

Heleen Hanssens ◽

Philippe Vanwolleghem ◽

Sophie Hernot ◽

...

Keyword(s):

Anion Exchange ◽

Anion Exchange Chromatography ◽

Exchange Chromatography ◽

In Vivo Studies ◽

Liver Uptake ◽

Organ Uptake ◽

Pharmacokinetic Properties ◽

Single Domain Antibodies ◽

The Impact

Single domain antibodies (sdAbs) have proven to be valuable probes for molecular imaging. In order to produce such probes, one strategy is the functionalization of the reactive amine side chain of lysines with a chelator, resulting in a mixture of compounds with a different degree of conjugation. In this study, we implemented anion exchange chromatography (AEX) to separate the different compounds or fractions that were further characterized and evaluated to study the impact of the conjugation degree on pharmacokinetic properties and functionality. Anti-HER2 and anti-MMR sdAbs were functionalized with NOTA or DTPA chelator. Anion exchange chromatography was performed using 0.02 mol/L Tris pH 7.5 as the first solvent and 0.25 M or 0.4 M NaCl (in case of NOTA chelator or DTPA chelator, respectively) as the second solvent applied as a gradient. The fractions were characterized via mass spectrometry (MS), surface plasmon resonance (SPR), and isoelectric focusing gel electrophoresis (IEF), while in vivo studies were performed after radiolabeling with either 68Ga (NOTA) or 111In (DTPA) to assess the impact of the conjugation degree on pharmacokinetics. AEX could successfully be applied to separate fractions of (chelator)n-anti-HER2 and (chelator)n-anti-MMR sdAb constructs. MS confirmed the identity of different peaks obtained in the separation process. SPR measurement suggests a small loss of affinity for (chelator)3-anti-sdAb, while IEF revealed a correlated decrease in isoelectric point (pI) with the number of conjugated chelators. Interestingly, both the reduction in affinity and in pI was stronger with the DTPA chelator than with NOTA for both sdAbs. In vivo data showed no significant differences in organ uptake for any construct, except for (DTPA)n-anti-MMR, which showed a significantly higher liver uptake for (DTPA)1-anti-MMR compared to (DTPA)2-anti-MMR and (DTPA)3-anti-MMR. For all constructs in general, high kidney uptake was observed, due to the typical renal clearance of sdAb-based tracers. The kidney uptake showed significant differences between fractions of a same construct and indicates that a higher conjugation degree improves kidney clearance. AEX allows the separation of sdAbs with a different degree of conjugation and provides the opportunity to further characterize individual fractions. The conjugation of a chelator to sdAbs can alter some properties of the tracers, such as pI; however, the impact on the general biodistribution profile and tumor targeting was minimal.

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Experimental Study of the Impact of Alisma plantago-aquatica Secretions on Pathogenic Bacteria

Agricultural science and practice ◽

10.15407/agrisp1.03.003 ◽

2014 ◽

Vol 1 (3) ◽

pp. 3-7

Author(s):

O. Zhukorskyy ◽

O. Hulay

Keyword(s):

Pathogenic Bacteria ◽

Initial Density ◽

Biologically Active ◽

Erysipelothrix Rhusiopathiae ◽

Natural Focus ◽

Test Species ◽

Popula Tions ◽

And Control ◽

The Impact

Aim. To estimate the impact of in vivo secretions of water plantain (Alisma plantago-aquatica) on the popula- tions of pathogenic bacteria Erysipelothrix rhusiopathiae. Methods. The plants were isolated from their natural conditions, the roots were washed from the substrate residues and cultivated in laboratory conditions for 10 days to heal the damage. Then the water was changed; seven days later the selected samples were sterilized using fi lters with 0.2 μm pore diameter. The dilution of water plantain root diffusates in the experimental samples was 1:10–1:10,000. The initial density of E. rhusiopathiae bacteria populations was the same for both experimental and control samples. The estimation of the results was conducted 48 hours later. Results. When the dilution of root diffusates was 1:10, the density of erysipelothrixes in the experimental samples was 11.26 times higher than that of the control, on average, the dilution of 1:100 − 6.16 times higher, 1:1000 – 3.22 times higher, 1:10,000 – 1.81 times higher, respectively. Conclusions. The plants of A. plantago-aquatica species are capable of affecting the populations of E. rhusiopathiae pathogenic bacteria via the secretion of biologically active substances into the environment. The consequences of this interaction are positive for the abovementioned bacteria, which is demon- strated by the increase in the density of their populations in the experiment compared to the control. The intensity of the stimulating effect on the populations of E. rhusiopathiae in the root diffusates of A. plantago-aquatica is re- ciprocally dependent on the degree of their dilution. The investigated impact of water plantain on erysipelothrixes should be related to the topical type of biocenotic connections, the formation of which between the test species in the ecosystems might promote maintaining the potential of natural focus of rabies. Keywords: Alisma plantago-aquatica, in vivo secretions, Erysipelothrix rhusiopathiae, population density, topical type of connections.

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Curcumin-containing Silver Nanoparticles prevent carbon tetrachlorideinduced hepatotoxicity in mice

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207323666201211100830 ◽

2020 ◽

Vol 23 ◽

Author(s):

Hossam Ebaid ◽

Mohamed Habila ◽

Iftekhar Hassan ◽

Jameel Al-Tamimi ◽

Mohamed S. Omar ◽

...

Keyword(s):

Dna Damage ◽

Silver Nanoparticles ◽

Nuclear Dna ◽

Liquid Paraffin ◽

Tail Length ◽

Hepatic Tissue ◽

Tissue Destruction ◽

Group 2 ◽

The Impact

Background: Hepatotoxicity remains an important clinical challenge. Hepatotoxicity observed in response to toxins and hazardous chemicals may be alleviated by delivery of the curcumin in silver nanoparticles (AgNPs-curcumin). In this study, we examined the impact of AgNPs-curcumin in a mouse model of carbon tetrachloride (CCl4)-induced hepatic injury. Methods: Male C57BL/6 mice were divided into three groups (n=8 per group). Mice in group 1 were treated with vehicle control alone, while mice in Group 2 received a single intraperitoneal injection of 1 ml/kg CCl4 in liquid paraffin (1:1 v/v). Mice in group 3 were treated with 2.5 mg/kg AgNPs-curcumin twice per week for three weeks after the CCl4 challenge. Results: Administration of CCL4 resulted in oxidative dysregulation, including significant reductions in reduced glutathione and concomitant elevations in the level of malondialdehyde (MDA). CCL4 challenge also resulted in elevated levels of serum aspartate transaminase (AST) and alanine transaminase (ALT); these findings were associated with the destruction of hepatic tissues. Treatment with AgNPs-curcumin prevented oxidative imbalance, hepatic dysfunction, and tissue destruction. A comet assay revealed that CCl4 challenge resulted in significant DNA damage as documented by a 70% increase in nuclear DNA tail-length; treatment with AgNPs-curcumin inhibited the CCL4-mediated increase in nuclear DNA tail-length by 34%. Conclusion: Administration of AgNPs-curcumin resulted in significant antioxidant activity in vivo. This agent has the potential to prevent the hepatic tissue destruction and DNA damage that results from direct exposure to CCL4.

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The design, synthesis, pharmacokinetic and pharmacodynamic evaluation of acyloxyalkyl-substituted T705 prodrugs

Medicinal Chemistry ◽

10.2174/1573406415666191022143933 ◽

2019 ◽

Vol 15 ◽

Author(s):

Xingzhou Li ◽

Tianhong Zhang ◽

Wu Zhong

Keyword(s):

Plasma Concentration ◽

Development Strategy ◽

Parent Compound ◽

Systemic Exposure ◽

Parent Drug ◽

New Drugs ◽

Structure Modification ◽

Design Synthesis ◽

Pharmacokinetic Properties

Background: The pharmacokinetic properties of T705 are not optimal for the development of new drugs. Objective: To improve the pharmacokinetic properties of T-705, structure modification of T-705 was conducted using a prodrug strategy. Method: The acidic amide H atom (N4-H) of T705 was attempted to be replaced with acyloxyalkyl groups following the prodrugs development strategy for carboxylic acids, and the resulting compounds were investigated whether could work as prodrugs and contribute to improving the pharmacokinetic properties of the parent compound T705 in vivo. Results: 4-acyloxyalkyl-T705 (4a–e), did act as prodrugs in vivo. 4-iso-butyryloxymethyl-T705 (4a) and 4-acetoxymethyl-T705 (4b) could significantly improve the plasma concentration and systemic exposure for T705, compound 4a displayed non inferior anti-influenza activities, compared with its parent drug T705. Conclusion: Our prodrugs development strategy for T705 is feasible, which may serves as a reference to prodrugs development of similar heterocyclic amides compounds.

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The impact of Zataria multiflora Boiss extract on in vitro and in vivo Th1/Th2 cytokine (IFN-γ/IL4) balance

Journal of Ethnopharmacology ◽

10.1016/j.jep.2013.10.003 ◽

2013 ◽

Vol 150 (3) ◽

pp. 1024-1031 ◽

Cited By ~ 35

Author(s):

Mohammad Hossein Boskabady ◽

Sakine Shahmohammadi Mehrjardi ◽

Abadorrahim Rezaee ◽

Houshang Rafatpanah ◽

Sediqeh Jalali

Keyword(s):

Zataria Multiflora ◽

Th2 Cytokine ◽

Ifn Γ ◽

The Impact

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Review: Impacts of shade on cattle well-being in the beef supply chain

Journal of Animal Science ◽

10.1093/jas/skaa375 ◽

2020 ◽

Author(s):

Lily N Edwards-Callaway ◽

M Caitlin Cramer ◽

Caitlin N Cadaret ◽

Elizabeth J Bigler ◽

Terry E Engle ◽

...

Keyword(s):

Supply Chain ◽

Heat Stress ◽

Beef Cattle ◽

Production Systems ◽

Construction Materials ◽

Well Being ◽

Third Party ◽

Ambient Temperatures ◽

Stress Susceptibility ◽

The Impact

ABSTRACT Shade is a mechanism to reduce heat load providing cattle with an environment supportive of their welfare needs. Although heat stress has been extensively reviewed, researched, and addressed in dairy production systems, it has not been investigated in the same manner in the beef cattle supply chain. Like all animals, beef cattle are susceptible to heat stress if they are unable to dissipate heat during times of elevated ambient temperatures. There are many factors that impact heat stress susceptibility in beef cattle throughout the different supply chain sectors, many of which relate to the production system, i.e. availability of shade, microclimate of environment, and nutrition management. The results from studies evaluating the effects of shade on production and welfare are difficult to compare due to variation in structural design, construction materials used, height, shape, and area of shade provided. Additionally, depending on operation location, shade may or may not be beneficial during all times of the year, which can influence the decision to make shade a permanent part of management systems. Shade has been shown to lessen the physiologic response of cattle to heat stress. Shaded cattle exhibit lower respiration rates, body temperatures, and panting scores compared to un-shaded cattle in weather that increases the risk of heat stress. Results from studies investigating the provision of shade indicate that cattle seek shade in hot weather. The impact of shade on behavioral patterns is inconsistent in the current body of research, some studies indicating shade provision impacts behavior and other studies reporting no difference between shaded and un-shaded groups. Analysis of performance and carcass characteristics across feedlot studies demonstrated that shaded cattle had increased ADG, improved feed efficiency, HCW, and dressing percentage when compared to cattle without shade. Despite the documented benefits of shade, current industry statistics, although severely limited in scope, indicate low shade implementation rates in feedlots and data in other supply chain sectors do not exist. Industry guidelines and third party on-farm certification programs articulate the critical need for protection from extreme weather but are not consistent in providing specific recommendations and requirements. Future efforts should include: updated economic analyses of cost versus benefit of shade implementation, exploration of producer perspectives and needs relative to shade, consideration of shade impacts in the cow-calf and slaughter plant segments of the supply chain, and integration of indicators of affective (mental) state and preference in research studies to enhance the holistic assessment of cattle welfare.

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The impact of FGF19/FGFR4 signaling inhibition in antitumor activity of multi-kinase inhibitors in hepatocellular carcinoma

Scientific Reports ◽

10.1038/s41598-021-84117-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hiroaki Kanzaki ◽

Tetsuhiro Chiba ◽

Junjie Ao ◽

Keisuke Koroki ◽

Kengo Kanayama ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Molecular Mechanisms ◽

Kinase Inhibitors ◽

Progression Free Survival ◽

Erk Signaling ◽

Enzyme Linked Immunosorbent Assay ◽

Antitumor Effects ◽

The Impact

AbstractFGF19/FGFR4 autocrine signaling is one of the main targets for multi-kinase inhibitors (MKIs). However, the molecular mechanisms underlying FGF19/FGFR4 signaling in the antitumor effects to MKIs in hepatocellular carcinoma (HCC) remain unclear. In this study, the impact of FGFR4/ERK signaling inhibition on HCC following MKI treatment was analyzed in vitro and in vivo assays. Serum FGF19 in HCC patients treated using MKIs, such as sorafenib (n = 173) and lenvatinib (n = 40), was measured by enzyme-linked immunosorbent assay. Lenvatinib strongly inhibited the phosphorylation of FRS2 and ERK, the downstream signaling molecules of FGFR4, compared with sorafenib and regorafenib. Additional use of a selective FGFR4 inhibitor with sorafenib further suppressed FGFR4/ERK signaling and synergistically inhibited HCC cell growth in culture and xenograft subcutaneous tumors. Although serum FGF19high (n = 68) patients treated using sorafenib exhibited a significantly shorter progression-free survival and overall survival than FGF19low (n = 105) patients, there were no significant differences between FGF19high (n = 21) and FGF19low (n = 19) patients treated using lenvatinib. In conclusion, robust inhibition of FGF19/FGFR4 is of importance for the exertion of antitumor effects of MKIs. Serum FGF19 levels may function as a predictive marker for drug response and survival in HCC patients treated using sorafenib.

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AMPK activates Parkin independent autophagy and improves post sepsis immune defense against secondary bacterial lung infections

Scientific Reports ◽

10.1038/s41598-021-90573-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Nathaniel B. Bone ◽

Eugene J. Becker ◽

Maroof Husain ◽

Shaoning Jiang ◽

Anna A. Zmijewska ◽

...

Keyword(s):

Bacterial Infections ◽

Pathogenic Bacteria ◽

Inflammatory Responses ◽

Abdominal Sepsis ◽

Immune Defense ◽

Bacterial Killing ◽

Lung Infections ◽

Sepsis Survivors ◽

The Impact

AbstractMetabolic and bioenergetic plasticity of immune cells is essential for optimal responses to bacterial infections. AMPK and Parkin ubiquitin ligase are known to regulate mitochondrial quality control mitophagy that prevents unwanted inflammatory responses. However, it is not known if this evolutionarily conserved mechanism has been coopted by the host immune defense to eradicate bacterial pathogens and influence post-sepsis immunosuppression. Parkin, AMPK levels, and the effects of AMPK activators were investigated in human leukocytes from sepsis survivors as well as wild type and Park2−/− murine macrophages. In vivo, the impact of AMPK and Parkin was determined in mice subjected to polymicrobial intra-abdominal sepsis and secondary lung bacterial infections. Mice were treated with metformin during established immunosuppression. We showed that bacteria and mitochondria share mechanisms of autophagic killing/clearance triggered by sentinel events that involve depolarization of mitochondria and recruitment of Parkin in macrophages. Parkin-deficient mice/macrophages fail to form phagolysosomes and kill bacteria. This impairment of host defense is seen in the context of sepsis-induced immunosuppression with decreased levels of Parkin. AMPK activators, including metformin, stimulate Parkin-independent autophagy and bacterial killing in leukocytes from post-shock patients and in lungs of sepsis-immunosuppressed mice. Our results support a dual role of Parkin and AMPK in the clearance of dysfunctional mitochondria and killing of pathogenic bacteria, and explain the immunosuppressive phenotype associated Parkin and AMPK deficiency. AMPK activation appeared to be a crucial therapeutic target for the macrophage immunosuppressive phenotype and to reduce severity of secondary bacterial lung infections and respiratory failure.

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