In Vitro Drug Absorption Enhancement Effects of Aloe vera and Aloe ferox

The co-administration of absorption enhancing agents with macromolecular drugs (e.g., protein and peptide drugs) has been identified as a means to improve the oral bioavailability of these drugs. Absorption-enhancing agents of natural origins have received a great deal of attention due to their sustainable production, in support of green chemistry. In previous studies, certain parts of the Aloe vera leaf (e.g., gel and whole leaf extract) have shown a potential to enhance drug permeation across the intestinal epithelial barrier. The mechanism of the drug-absorption-enhancement action and the capacity for absorption-enhancement of the A. vera gel and whole leaf, were investigated in this study. A clear decrease in transepithelial electrical resistance (TEER) of Caco-2 cell monolayers exposed to A. vera gel and wholeleaf extract, in various concentrations, indicated the opening of tight junctions between the epithelial cells. The transport of Fluorescein isothiocyanate (FITC)-dextran, with a molecular weight of 4 kDa (FD-4), could be enhanced across the Caco-2 cell monolayers, by the A. vera gel and whole-leaf extract, but not the FITC-dextran with larger molecular weights (i.e., 10, 20, and 40 kDa), which indicated a limited drug absorption enhancement capacity, in terms of the molecular size. Accumulation of FD-4 between the Caco-2 cells (and not within the cells), after treatment with the A. vera gel and whole-leaf extract was shown with a confocal laser scanning microscopy (CLSM) imaging, indicating that the paracellular transport of FD-4 occurred after the interaction of the A. vera gel and whole-leaf extract, with the epithelial cell monolayers. Furthermore, changes in the F-actin distribution in the cytoskeleton of the Caco-2 cell monolayers was observed by means of a fluorescence staining, which confirmed tight junction modulation as the mechanism of action for the absorption enhancement effect of the A. vera gel and whole-leaf extract.

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Permeation enhancement effects of leaf materials from different aloe species on in vitro and ex vivo nasal epithelial models

Journal of Herbmed Pharmacology ◽

10.34172/jhp.2020.45 ◽

2020 ◽

Vol 9 (4) ◽

pp. 355-365

Author(s):

Werner Gerber ◽

Dewald Steyn ◽

Awie Kotzé ◽

Hanna Svitina ◽

Ché Weldon ◽

...

Keyword(s):

Drug Delivery ◽

Oral Drug Delivery ◽

Cell Model ◽

Ex Vivo ◽

Aloe Vera ◽

Neutral Red ◽

Oral Drug ◽

Nasal Drug Delivery ◽

Aloe Ferox

Introduction: The nasal route of drug administration offers an alternative way for oral drug delivery and has the benefit of avoiding first-pass metabolism through drug delivery directly into the systemic circulation. The drug absorption enhancing effects of selected aloe leaf materials have been shown across various delivery routes, but their efficacies in this regard across nasal epithelia have not yet been investigated. The aim of this study was to determine the effects of gel and whole leaf extract materials from three selected aloe species (Aloe vera, Aloe ferox and Aloe muth-muth) on FITC-dextran 4400 permeation across two nasal epithelial models. Methods: Permeation of FITC-dextran 4400 and histological studies were conducted on both RPMI 2650 cell layers and excised sheep nasal mucosa, while toxicity studies were conducted using a neutral red assay on the RPMI 2650 cell model. Results: Significantly increased (P ≤ 0.05) apparent permeability coefficient (Papp) values of FITC-dextran 4400 in the presence of the aloe materials as compared to the control were found with all three aloe species at the highest concentrations (1.5% and 3% w/v) in the RPMI 2650 cell line, while only Aloe muth-muth at the highest concentration exhibited significantly (P ≤ 0.05) higher Papp values across the excised tissue model. Histological and neutral red analysis showed that Aloe vera materials exhibited detrimental effects, Aloe muth-muth only showed slight effects on cell viability and Aloe ferox exhibited no effect on the nasal epithelium. Conclusion: This in vitro study showed for the first time the potential of Aloe ferox and Aloe muth-muth leaf materials to enhance nasal drug delivery without causing damaging effects on the epithelium, while Aloe vera enhanced nasal drug delivery with detrimental effects as determined by means of cytotoxicity assays and histological analysis.

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Wound Healing Effects of Aloe muth-muth: In Vitro Investigations Using Immortalized Human Keratinocytes (HaCaT)

Biology ◽

10.3390/biology9110350 ◽

2020 ◽

Vol 9 (11) ◽

pp. 350

Author(s):

Morné Fouché ◽

Clarissa Willers ◽

Sias Hamman ◽

Christiaan Malherbe ◽

Jan Steenekamp

Keyword(s):

Wound Healing ◽

Hacat Cell ◽

Aloe Vera ◽

Human Keratinocytes ◽

Assay Method ◽

Traditional Use ◽

Cell Line Cell ◽

Aloe Ferox ◽

Cultivated Species

The traditional use of Aloe spp. for the purpose of wound healing has a long history and is widespread internationally. Recently, a hybrid aloe plant (Aloe muth-muth) has been cultivated by cross pollination between Aloe vera and Aloe ferox. The Aloe muth-muth plant has not yet been investigated for medicinal properties and provides an opportunity for potential biological activity, including wound healing. The aim of this study was to investigate the in vitro wound healing effects of both Aloe muth-muth gel and whole leaf material with the use of the immortalized human keratinocyte (HaCaT) cell line. Cell viability was conducted using methyl thiazolyl tetrazolium (MTT) assays. In vitro wound healing was tested on HaCaT cells using an established scratch assay method. The effect of Aloe muth-muth gel material on HaCaT cell migration was also investigated. Aloe muth-muth gel material exhibited statistically significantly (p < 0.05) higher percentage wound closure compared to the control at all three concentrations investigated. These findings confirm that this newly cultivated species, Aloe muth-muth, also possesses wound healing activity corresponding to that reported for the two species it is derived from, namely, Aloe vera and Aloe ferox. Therefore, Aloe muth-muth has the potential to be used in future wound therapeutics.

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Screening, Fabrication and Evaluation of Pharmaceutical Dosage Forms using P-Glycoprotein Modulators

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2017.10.2.8 ◽

2017 ◽

Vol 10 (2) ◽

pp. 3688-3699

Author(s):

Joshi Vedamurthy ◽

Shivakumar Inamdar ◽

Ankit Acharya ◽

Rajesh Kowti

Keyword(s):

Cell Lines ◽

Tinospora Cordifolia ◽

Absorption Enhancement ◽

Synergistic Activity ◽

Capsicum Frutescens ◽

Plumbago Zeylanica ◽

Pharmaceutical Dosage Forms ◽

Holarrhena Antidysenterica ◽

Trachyspermum Ammi

In this project, in vitro absorption enhancement activity of P-gp substrates Fexofenadine (Fx) and Ciprofloxacin (Cp) were evaluated in everted rat gut sac model and Caco-2 cell lines. Verapamil was used as P-gp inhibitor. Piper betel, Trachyspermum ammi, Plumbago zeylanica, Trikatu, Moringaoleifera, Murraya koenigii, Ferulafoitida Zingiber officinale, Cheilocostus speciosus, Capsicum frutescens Operculina turpethum Holarrhena antidysenterica Mesuaferrea, Tinospora cordifolia, and Picrorhiza kurroa, were selected and extracted with 99% alcohol and fresh juices of Citrus limon, Punica granatum seeds were also studied. In-vitro studies depicted that Fexofenadine and Ciprofloxacin absorption was increased greater than 20% in the presence of Operculinaturpethum, Capsicum frutescens, Holarrhena Antidysenterica, Tinospora cordifolia, Trikatu, Trachyspermum ammi, Plumbago zeylanica. The flux of the ciprofloxacin transport was in the range of 9-23 mcg/min and Papp 2.6 × 10-5 cm/sec to 4.1 × 10-5 cm/sec whereas Fexofenadine flux was in the range of 2-7.7 mcg/min and Papp 4.16 × 10–6 cm/sec to 1.62 × 10-5 cm/sec. In vitro antimicrobial activity of ciprofloxacin on selected microbes in presence of extracts also depicted synergistic activity. Histological studies revealed that there is no significant variation observed in the isolated sac in presence of the extracts. CaCo2 cell lines studies showed that, formulation enhanced the absorption of fexofenadine greater than 50%. Tablets were prepared and evaluated using the plant extracts which yielded >20% absorption enhancement of the substrates. In conclusion, tablet formulation containing the alcoholic extracts of Trachyspermum ammi, Plumbago zylanicum, Capsicum frutescens, Operculina turpethum, Holarrhena Antidysenterica, Tinospora cordifolia and Trikatu can act as an absorption enhancer for fexofenadine and ciprofloxacin. The mechanism of action of these herbs could be due to P-gp inhibition. Further clinical studies are needed to prove its efficacy in humans.

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Evaluation of Isolated Fractions of Aloe vera Gel Materials on Indinavir Pharmacokinetics: In vitro and in vivo Studies

Current Drug Delivery ◽

10.2174/1567201813888160302163208 ◽

2016 ◽

Vol 13 (3) ◽

pp. 471-480 ◽

Cited By ~ 5

Author(s):

Lonette Wallis ◽

Maides Malan ◽

Chrisna Gouws ◽

Dewald Steyn ◽

Suria Ellis ◽

...

Keyword(s):

Aloe Vera ◽

In Vivo Studies ◽

Aloe Vera Gel

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Novel Swellable/Expandable Gastroretentive Floating Films of Gliclazide Folded in Capsule Shell for the Effective Management of Diabetes Mellitus: Formulation Development, Optimization and In vitro Evaluation

Current Drug Therapy ◽

10.2174/1574885515999201201122710 ◽

2020 ◽

Vol 15 ◽

Author(s):

Diksha Sharma ◽

Deepak Sharma

Keyword(s):

Diabetes Mellitus ◽

Drug Absorption ◽

Gastric Fluid ◽

Stability Study ◽

Gastric Retention ◽

Effective Management ◽

In Vitro Evaluation ◽

Capsule Shell ◽

Study Results

Background: Gliclazide (GLZ) belongs to the second-generation of sulphonylureas, is a drug of choice for the management of type II DM. It belongs to BCS Class II. The major site of drug absorption for GLZ is the stomach; it displayed variation in the drug absorption rate and bioavailability due to the shorter gastric retention time. Floating mechanism performance gets affected when the gastric fluid level not sufficiently higher, which ultimately obstructs the floating behavior, which is the major limitation of reported formulations. This limitation can get over by folded the film into the capsule shell that dissolved in gastric fluid and film swell/expands to dimensions higher than pylorus sphincter (12mm), thus prevents its evacuation. Objective: To explore the floating mechanism in the designing of films along with a tendency to expand by swelling and unfolding by utilizing a mixture of hydrophilic and hydrophobic polymer to achieve the controlled drug delivery and prolonged gastric retention of drug. Methods: The gastroretentive floating films were formulated by the solvent casting technique using 32 full factorial design and subjected to in vitro evaluation parameters, drug-excipient compatibility, X-ray diffraction and accelerated stability study. Results: The pre-formulation study established the purity and identification of drug. FTIR study confirmed no drug excipient interaction. F3, F6, and F9 were optimized based on in vitro floating characteristics, swelling/expanding ability, and unfolding time study. All developed formulations were unfolded within 14-22 min after capsule disintegration. The F3 was selected as final formulation as its ability to control the release of drug for 24 hrs followed by Zero-order kinetics having super case 2 transport. XRD confirmed the amorphousness of drug within formulation. The stability study results revealed that formulation was quite stable at extreme storage condition. Conclusion: The developed novel formulation has a good potential for the effective management and treatment of Diabetes Mellitus.

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Microstructural and histochemical variations during in vitro to in vivo plant developments in Aloe vera (L.) Burm.f (Xanthorrhoeaceae)

Industrial Crops and Products ◽

10.1016/j.indcrop.2020.113162 ◽

2020 ◽

pp. 113162

Author(s):

Manokari M. ◽

Priyadharshini S. ◽

Mahipal S. Shekhawat

Keyword(s):

Aloe Vera

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Generation of tetracycline-controllable CYP3A4-expressing Caco-2 cells by the piggyBac transposon system

Scientific Reports ◽

10.1038/s41598-021-91160-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Moe Ichikawa ◽

Hiroki Akamine ◽

Michika Murata ◽

Sumito Ito ◽

Kazuo Takayama ◽

...

Keyword(s):

Small Intestine ◽

Drug Absorption ◽

Cell Model ◽

Negative Effects ◽

Piggybac Transposon ◽

Drug Metabolizing Enzyme ◽

Metabolizing Enzyme ◽

Cyp3a4 Expression

AbstractCaco-2 cells are widely used as an in vitro intestinal epithelial cell model because they can form a monolayer and predict drug absorption with high accuracy. However, Caco-2 cells hardly express cytochrome P450 (CYP), a drug-metabolizing enzyme. It is known that CYP3A4 is the dominant drug-metabolizing enzyme in human small intestine. In this study, we generated CYP3A4-expressing Caco-2 (CYP3A4-Caco-2) cells and attempted to establish a model that can simultaneously evaluate drug absorption and metabolism. CYP3A4-Caco-2 cells were generated by piggyBac transposon vectors. A tetracycline-controllable CYP3A4 expression cassette (tet-on system) was stably transduced into Caco-2 cells, thus regulating the levels of CYP3A4 expression depending on the doxycycline concentration. The CYP3A4 expression levels in CYP3A4-Caco-2 cells cultured in the presence of doxycycline were similar to or higher than those of adult small intestine. The CYP3A4-Caco-2 cells had enough ability to metabolize midazolam, a substrate of CYP3A4. CYP3A4 overexpression had no negative effects on cell proliferation, barrier function, and P-glycoprotein activity in Caco-2 cells. Thus, we succeeded in establishing Caco-2 cells with CYP3A4 metabolizing activity comparable to in vivo human intestinal tissue. This cell line would be useful in pharmaceutical studies as a model that can simultaneously evaluate drug absorption and metabolism.

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Drug Disposition in the Lower Gastrointestinal Tract: Targeting and Monitoring

Pharmaceutics ◽

10.3390/pharmaceutics13020161 ◽

2021 ◽

Vol 13 (2) ◽

pp. 161

Author(s):

Glenn Lemmens ◽

Arno Van Camp ◽

Stephanie Kourula ◽

Tim Vanuytsel ◽

Patrick Augustijns

Keyword(s):

Drug Absorption ◽

Drug Disposition ◽

Drug Stability ◽

Ussing Chamber ◽

Dissolution Kinetics ◽

Comprehensive Overview ◽

Drug Molecules ◽

Epithelial Physiology

The increasing prevalence of colonic diseases calls for a better understanding of the various colonic drug absorption barriers of colon-targeted formulations, and for reliable in vitro tools that accurately predict local drug disposition. In vivo relevant incubation conditions have been shown to better capture the composition of the limited colonic fluid and have resulted in relevant degradation and dissolution kinetics of drugs and formulations. Furthermore, drug hurdles such as efflux transporters and metabolising enzymes, and the presence of mucus and microbiome are slowly integrated into drug stability- and permeation assays. Traditionally, the well characterized Caco-2 cell line and the Ussing chamber technique are used to assess the absorption characteristics of small drug molecules. Recently, various stem cell-derived intestinal systems have emerged, closely mimicking epithelial physiology. Models that can assess microbiome-mediated drug metabolism or enable coculturing of gut microbiome with epithelial cells are also increasingly explored. Here we provide a comprehensive overview of the colonic physiology in relation to drug absorption, and review colon-targeting formulation strategies and in vitro tools to characterize colonic drug disposition.

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