Acute toxicity study of a polysaccharide based hydrogel from linseed for potential use in drug delivery system

Flaxseed (Linum usitatissimum) mucilage: A versatile stimuli-responsive functional biomaterial for pharmaceuticals and healthcare

The present review is novel as it discusses the main findings of researchers on the topic and their implications, as well as highlights the emerging research in this particular area and its future prospective. The seeds of Flax (Linum usitatissimum) extrude mucilage (FSM) that has a diverse and wide range of applications, especially in the food industry and as a pharmaceutical ingredient. FSM has been blended with several food and dairy products to improve gelling ability, optical properties, taste, and user compliance. The FSM is recognized as a foaming, encapsulating, emulsifying, suspending, film-forming, and gelling agent for several pharmaceutical preparations and healthcare materials. Owing to stimuli (pH) -responsive swelling-deswelling characteristics, high swelling indices at different physiological pHs of the human body, and biocompatibility, FSM is considered a smart material for intelligent, targeted, and controlled drug delivery applications through conventional and advanced drug delivery systems. FSM has been modified through carboxymethylation, acetylation, copolymerization, and electrostatic complexation to get the desired properties for pharma, food, and healthcare products. The present review is therefore devoted to the isolation techniques, structural characterization, highly valuable properties for food and pharmaceutical industries, preclinical and clinical trials, pharmacological aspects, biomedical attributes, and patents of FSM.

Folate decorated lipid chitosan hybrid nanoparticles of 5-fluorouracil for enhanced anticancer efficacy against colon cancer

The study aimed to develop folate decorated lipid chitosan hybrid nanoparticles for targeted delivery of 5-fluorouracil in colon cancer by utilizing the overexpressed folate receptors on the surface of HT-29 and HCT 116 cancer cell lines. The developed formulations were prepared by the ionic gelation method with slight modifications. The developed formulations exhibited spherical morphology, smaller particle size (158 to 225 nm), zeta potential (32.24 to 35.95 mV), PDI (0.19 to 0.35), and high encapsulation efficiency (85.3 % to 94.2 %) with optimal physicochemical characteristics. The in vitro release showed a biphasic release pattern with an initial burst release followed by a sustained release for 48 h. Moreover, the in vitro cell line study revealed that FA-CLPN-2 exhibited an enhanced cellular uptake and greater cytotoxic effect in HT-29 and HCT 116 cell lines compared to non-targeted CLPN-2 and free drug solution due to the folate receptor facilitated endocytosis process. The in vivo toxicity study revealed the safety and biocompatibility of the developed formulations in biological systems. The stability study demonstrates the stability of the developed formulations. Overall, these results suggest that the folate decorated lipid chitosan hybrid nanoparticles could be used as a potential delivery system for tumor-targeted therapy with reduced side effects.

A comprehensive review of flaxseed (Linum usitatissimum L.): health-affecting compounds, mechanism of toxicity, detoxification, anticancer and potential risk

Flaxseed consumption (Linum usitatissimum L.) has increased due to its potential health benefits, such as protection against inflammation, diabetes, cancer, and cardiovascular diseases. However, flaxseeds also contains various anti-nutritive and toxic compounds such as cyanogenic glycosides, and phytic acids etc. In this case, the long-term consumption of flaxseed may pose health risks due to these non-nutritional substances, which may be life threatening if consumed in high doses, although if appropriately utilized these may prevent/treat various diseases by preventing/inhibiting and or reversing the toxicity induced by other compounds. Therefore, it is necessary to remove or suppress the harmful and anti-nutritive effects of flaxseeds before these are utilized for large-scale as food for human consumption. Interestingly, the toxic compounds of flaxseed also undergoes biochemical detoxification in the body, transforming into less toxic or inactive forms like α-ketoglutarate cyanohydrin etc. However, such detoxification is also a challenge for the development, scalability, and real-time quantification of these bioactive substances. This review focuses on the health affecting composition of flaxseed, along with health benefits and potential toxicity of its components, detoxification methods and mechanisms with evidence supported by animal and human studies.

pH Sensitive Pluronic Acid/Agarose-Hydrogels as Controlled Drug Delivery Carriers: Design, Characterization and Toxicity Evaluation

The objective of this study was to fabricate and evaluate a pH sensitive cross-linked polymeric network through the free radical polymerization technique for the model drug, cyclophosphamide, used in the treatment of non-Hodgkin's lymphoma. The Hydrogels were prepared using a polymeric blend of agarose, Pluronic acid, glutaraldehyde, and methacrylic acid. The prepared hydrogels were characterized for drug loading (%), swelling pattern, release behavior, the ingredient's compatibility, structural evaluation, thermal integrity, and toxicity evaluation in rabbits. The new polymer formation was evident from FTIR findings. The percentage loaded into the hydrogels was in the range of 58.65-75.32%. The developed hydrogels showed significant differences in swelling dynamics and drug release behavior in simulated intestinal fluid (SIF) when compared with simulated gastric fluid (SGF). The drug release was persistent and performed in a controlled manner for up to 24 h. A toxicity study was conducted on white albino rabbits. The developed hydrogels did not show any signs of ocular, skin, or oral toxicity; therefore, these hydrogels can be regarded as safe and potential carriers for controlled drug delivery in biomedical applications.

Fabrication, Characterization and Toxicity Evaluation of Chemically Cross linked Polymeric Network for Sustained Delivery of Metoprolol Tartrate

Natural mucilages are auspicious biodegradable polymeric materials. The aim of the present research work was to elucidate the characteristics of quince mucilage-based polymeric network for sustained delivery of metprolol tartrate and its toxicity evaluation. Mucilage was extracted by hot water extraction, and characterization of quince mucilage was accomplished by using Fourier transform infrared (FTIR) spectroscopy. Different batches of quince mucilage polymeric network were prepared by free radical polymerization by utilizing varying ratios of quince mucilage, acrylamide and crosslinker. Degree of swelling depends on concentration of mucilage, monomer and also on crosslinking density of polymeric network. FTIR illustrates proficient grafting, and morphological (scanning electron microscopy) analysis signified porous design. Hence, quince mucilage-based design was encouraging for sustained delivery of metprolol tartrate and acute toxicity evaluation proved that mucilage-based network was safe for oral drug delivery system.

β-cyclodextrin chitosan-based hydrogels with tunable pH-responsive properties for controlled release of acyclovir: design, characterization, safety, and pharmacokinetic evaluation

In this work, series of pH-responsive hydrogels (FMA1-FMA9) were synthesized, characterized, and evaluated as potential carrier for oral delivery of an antiviral drug, acyclovir (ACV). Different proportions of β-cyclodextrin (β-CD), chitosan (CS), methacrylic acid (MAA) and N' N'-methylenebis-acrylamide (MBA) were used to fabricate hydrogels via free radical polymerization technique. Fourier transform infrared spectroscopy confirmed fabrication of new polymeric network, with successful incorporation of ACV. Scanning electron microscopy (SEM) indicated presence of slightly porous structure. Thermal analysis indicated enhanced thermal stability of polymeric network. Swelling studies were carried out at 37 °C in simulated gastric and intestinal fluids. The drug release data was found best fit to zero-order kinetics. The preliminary investigation of developed hydrogels showed a pH-dependent swelling behavior and drug release pattern. Acute oral toxicity study indicated no significant changes in behavioral, clinical, or histopathological parameters of Wistar rats. Pharmacokinetic study indicated that developed hydrogels caused a significant increase in oral bioavailability of ACV in rabbit plasma as compared to oral suspension when both were administered at a single oral dose of 20 mg kg-1 bodyweight. Hence, developed hydrogel formulation could be used as potential candidate for controlled drug delivery of an antiviral drug acyclovir.

Biodegradable and biocompatible polymeric nanoparticles for enhanced solubility and safe oral delivery of docetaxel: In vivo toxicity evaluation

Docetaxel (DTX) is a chemotherapeutic drug with poor hydrophilicity and permeability. Its lipophilic properties decrease its absorption in systemic circulation which hinders its therapeutic efficacy & safety. Cyclodextrins (CDs) with their unique structural properties enhance solubility of chemotherapeutic drugs. The study was designed to formulate docetaxel-cyclodextrins inclusion complexes for enhancement of solubility with sulfobutyl ether β-cyclodextrin (SBE₇-β-CD), hydroxypropyl β-cyclodextrin (HP-β-CD) and β-cyclodextrin (β-CD). Further, by using ionic gelation method polymeric nanoparticles of docetaxel-cyclodextrins were prepared with sodium tri poly phosphate (STPP) and chitosan (CS). Optimization is performed by varying CS and STPP mass ratios. Nanoparticles were analyzed for their physicochemical properties, drug-excipient compatibility, thermal stability and oral toxicity. CDs enhanced the solubility of DTX. Nanoparticles were found within 144.8 ± 65.19 - 372.0 ± 126.9 nm diameters with polydispersity ranging 0.117-0.375. The particles were found round & circular in shape with smooth and non-porous surface. Increased quantity of drug release was observed from DTX-CDs loaded nanoparticles than pure drug loaded nanoparticles. Oral toxicity in rabbits revealed biochemical, histopathological profile with no toxic effect on cellular structure of animals.

Linseed hydrogel based floating drug delivery system for fluoroquinolone antibiotics: Design, in vitro drug release and in vivo real-time floating detection

Herein, we designed a novel gastroretentive drug delivery system as floating matrix tablets based on a polysaccharide material from linseeds (Linum usitatissimum L.) for fluoroquinolone antibiotics. A number of formulations were designed with a combination of linseed hydrogel (LSH) and different excipients to obtain a desired sustained release profile of moxifloxacin. The drug release study was performed basically at pH 1.2. However, the tablet may pass through the stomach to intestine due to certain reasons then it also offered sustained drug release at intestinal pH 4.5, 6.8 and 7.4, as well. Results indicated that sustained moxifloxacin release was directly proportional to the concentration of LSH and the release of drug followed non-Fickian diffusion. SEM of the tablets indicated porous nature of LSH with elongated channels which contributed to the swelling of the tablet and then facilitated the discharge of moxifloxacin from the core of the tablet. In vivo X-ray study was performed to assess disintegration and real-time floating of tablet that confirmed its presence for 6 h in the stomach. These findings indicated that LSH can be used to develop novel gastroretentive sustained release drug delivery systems with the double advantage of sustained drug release at all pH of GIT.

Diligent profiling of preclinical safety of the silk protein sericin

BACKGROUND

Sericin is a widely used protein in the pharmaceutical industry derived from the silkworm, Bombyx mori, and used for the treatment of various diseases and pathological conditions. It is the main ingredient of the Unani preparation khameera abresham. The study was conducted to evaluate the preclinical toxicity of the silk protein sericin in mice.

METHODS

In the acute toxicity study, sericin was administered once orally to different groups of animals at doses of 500, 1000, and 2000 mg/kg. Animals were observed for 14 days. In the sub-acute toxicity study, sericin was administered in mice for 4 weeks in the toxic group at doses of 500, 1000, and 2000 mg/kg, while in the recovery group it was administered for 4 weeks at doses of 500 and 2000 mg/kg followed by 2 weeks of distilled water administration.

RESULTS

In the acute toxicity study, the observed parameters showed no significant difference, and no mortality was reported. In the sub-acute toxicity study, there were no toxicological effects in any of the estimated parameters, while histopathological analysis showed inflammation in vital organs at the dose of 2000 mg/kg.

CONCLUSIONS

Results of our acute toxicity study suggest that sericin is safe at all administered doses, while the sub-acute study suggests that the NOAEL (no-observed-adverse-effect level) of sericin is below 2000 mg/kg, at which it can be considered safe.