Biodegradable chitosan-based ambroxol hydrochloride microspheres: effect of cross-linking agents

Emerging horizons and prospects of polysaccharide-constructed gels in the realm of wound healing

Polysaccharides, with the abundant availability, biodegradability, and inherent safety, offer a vast array of promising applications. Leveraging the remarkable attributes of polysaccharides, biomimetic and multifunctional hydrogels have emerged as a compelling avenue for efficacious wound dressing. The gels emulate the innate extracellular biomatrix as well as foster cellular proliferation. The distinctive structural compositions and profusion of functional groups within polysaccharides confer excellent physical/chemical traits as well as distinct restorative involvements. Gels crafted from polysaccharide matrixes serve as a robust defense against bacterial threats, effectively shielding wounds from harm. This comprehensive review delves into wound physiology, accentuating the significance of numerous polysaccharide-based gels in the wound healing context. The discourse encompasses an exploration of polysaccharide hydrogels tailored for diverse wound types, along with an examination of various therapeutic agents encapsulated within hydrogels to facilitate wound repair, incorporating recent patent developments. Within the scope of this manuscript, the perspective of these captivating gels for promoting optimal healing of wounds is vividly depicted. Nevertheless, the pursuit of knowledge remains ongoing, as further research is warranted to bioengineer progressive polysaccharide gels imbued with adaptable features. Such endeavors hold the promise of unlocking substantial potential within the realm of wound healing, propelling us toward multifaceted and sophisticated solutions.

Ambroxol Hydrochloride Loaded Gastro-Retentive Nanosuspension Gels Potentiate Anticancer Activity in Lung Cancer (A549) Cells

This study aimed to develop gastro-retentive sustained-release ambroxol (ABX) nanosuspensions utilizing ambroxol-kappa-carrageenan (ABX-CRG_K) complexation formulations. The complex was characterized by differential scanning calorimetry, powder x-ray diffractometer, and scanning electron microscopy. The prepared co-precipitate complex was used for the development of the sustained-release formulation to overcome the high metabolic and poor solubility problems associated with ABX. Furthermore, the co-precipitate complex was formulated as a suspension in an aqueous floating gel-forming vehicle of sodium alginate with chitosan, which might be beneficial for targeting the stomach as a good absorption site for ABX. The suspension exhibited rapid floating gel behaviour for more than 8 h, thus confirming the gastro-retentive effects. Particle size analysis revealed that the optimum nanosuspension (ABX-NS) had a mean particle size of 332.3 nm. Afterward, the ABX released by the nanoparticles would be distributed to the pulmonary tissue as previously described. Based on extensive pulmonary distribution, the developed nanosuspension-released ABX nanoparticles showed significant cytotoxic enhancement compared to free ABX in A549 lung cancer cells. However, a significant loss of mitochondrial membrane potential (MMP) also occurred. The level of caspase-3 was the highest in the ABX-NS-released particle-treated samples, with a value of 416.6 ± 9.11 pg/mL. Meanwhile, the levels of nuclear factor kappa beta, interleukins 6 and 1 beta, and tumour necrosis alpha (NF-kB, IL-6, IL-1β, and TNF-α, respectively) were lower for ABX-NS compared to free ABX (p < 0.05). In caspase-3, Bax, and p53, levels significantly increased in the presence of ABX-NS compared to free ABX. Overall, ABX-NS produced an enhancement of the anticancer effects of ABX on the A549 cells, and the developed sustained-release gel was successful in providing a gastro-retentive effect.

Mucoadhesive gastroretentive microparticulate system for programmed delivery of famotidine and clarithromycin

AIM

The present research was aimed to develop thiolated polyacrylic acid (TPA) based microspheres (MSPs) containing famotidine (FX) and clarithromycin (CLX).

METHODS

TPA was synthesised from polyacrylic acid and l-cysteine in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDAC). The prepared TPA was characterised using FT-IR (Fourier transform-infra red), ¹H-NMR (proton nuclear magnetic resonance) spectroscopy, P-XRD (powder X ray diffraction) method, and zeta potential. The analytical tools have supported the formation of TPA. The thiolated microspheres were prepared by emulsion solvent evaporation method using 0.75% w/v polymer concentration and stirring at 400 rpm for 8 hr.

RESULTS

The average particle size and zeta potential of optimised formulation was found to be 25.2 ± 1.87 μm and -26.68 mV, respectively. The entrapment efficiency of the optimised formulation was obtained 67.20% for FX and 70.20% for CLX. The developed microspheres were swelled only in 4 h from 0.5 to 0.9. The in vitro mucoadhesive study and in vitro drug release studies demonstrated that microspheres showed mucoadhesive property. In in vitro drug release studies, the release of FX and CLX were observed to be 58.68% and 60.48%, respectively from microspheres in 8 h. The thiolated microspheres showed higher adhesion time (7.0 ± 0.8 h) in comparison to the plain microspheres (2.6 ± 0.4 h).

CONCLUSION

The prepared TPA based mucoadhesive microspheres can be utilised as carriers for the treatment of peptic ulcer caused by Helicobacter pylori which will offer enhanced residence time for the rational drug combination in the gastric region.

Technologies and Formulation Design of Polysaccharide-Based Hydrogels for Drug Delivery

Polysaccharide-based hydrogel particles (PbHPs) are very promising carriers aiming to control and target the release of drugs with different physico-chemical properties. Such delivery systems can offer benefits through the proper encapsulation of many drugs (non-steroidal and steroidal anti-inflammatory drugs, antibiotics, etc) ensuring their proper release and targeting. This review discusses the different phases involved in the production of PbHPs in pharmaceutical technology, such as droplet formation (SOL phase), sol-gel transition of the droplets (GEL phase) and drying, as well as the different methods available for droplet production with a special focus on prilling technique. In addition, an overview of the various droplet gelation methods with particular emphasis on ionic cross-linking of several polysaccharides enabling the formation of particles with inner highly porous network or nanofibrillar structure is given. Moreover, a detailed survey of the different inner texture, in xerogels, cryogels or aerogels, each with specific arrangement and properties, which can be obtained with different drying methods, is presented. Various case studies are reported to highlight the most appropriate application of such systems in pharmaceutical field. We also describe the challenges to be faced for the breakthrough towards clinic studies and, finally, the market, focusing on the useful approach of safety-by-design (SbD).

Relationship Between Expression of Proteins ERCC1, ERCC2, and XRCC1 and Clinical Outcomes in Patients with Rectal Cancer Treated with FOLFOX-Based Preoperative Chemoradiotherapy

BACKGROUND

Platinum resistance enhances DNA damage repair through nucleotide excision repair mechanisms involving the excision repair cross-complementing group 1 (ERCC1), X-ray cross-complementing group 1 (XRCC1), and excision repair cross-complementing group 2 (ERCC2). We evaluated the correlation between the expression of these three DNA repair genes and clinical outcomes in patients with rectal cancer receiving FOLFOX-based preoperative chemoradiotherapy (CRT).

METHODS

Using immunohistochemistry, we examined the expression of ERCC1, ERCC2, and XRCC1 in pre-CRT cancer tissues from 86 patients with rectal cancer who had undergone curative resection and preoperative CRT with FOLFOX-4 to identify potential predictors of clinical outcomes.

RESULTS

Following CRT, 57 and 29 patients were classified as responders (pathological tumor regression grade TRG 0 and TRG 1) and poor responders (TRG 2 and TRG 3), respectively. The multivariate analysis revealed that ERCC1 overexpression was correlated with a poor CRT response [p < 0.0001; odds ratio (OR), 9.397; 95% confidence interval (CI) 2.721-32.457]. Furthermore, a poor response to CRT (pathological TRG of 2-3) (p = 0.18; OR 5.685; 95% CI 1.349-23.954) and abnormal pre-CRT serum carcinoembryonic antigen levels (>5 ng/mL) (p = 0.03; OR 6.288; 95% CI 1.198-33.006) were independent predictors of postoperative relapse. By contrast, ERCC2 and XRCC1 expression did not play predictive roles in the analyzed patients.

CONCLUSIONS

ERCC1 overexpression is associated with a poor preoperative CRT response in patients with rectal cancer receiving FOLFOX-based preoperative CRT. ERCC1 is a potential biomarker for identifying patients who can benefit from customized treatment programs.

Fabrication and cell viability of injectable n-HA/chitosan composite microspheres for bone tissue engineering

The n-HA/CS microspheres exhibit good properties while supporting cell growth, thus acting as a promising injectable matrix for bone tissue engineering.

Predictive value of ERCC1, ERCC2, and XRCC1 overexpression for stage III colorectal cancer patients receiving FOLFOX-4 adjuvant chemotherapy

OBJECTIVES

To determine the correlation between expression of three DNA repair genes and early failure/clinical outcome of stage III colorectal cancer (CRC) patients administrated with FOLFOX-4, including the excision repair cross-complementation group 1 (ERCC1), the excision repair cross-complementing 2 (ERCC2), and X-ray repair cross-complementing protein 1 (XRCC1).

MATERIALS AND METHODS

We retrospectively analyzed clinicopathological features and ERCC1, ERCC2, XRCC1 expressions by immunohistochemical staining in 180 stage III CRC patients undergoing curative resection and treated with FOLFOX-4 chemotherapy to identify predictors of postoperative early failure.

RESULTS

Among 180 CRC patients, 44 patients were classified into early failure group, and 136 patients were categorized into non-early failure group. A multivariate logistic regression analysis showed that ERCC1 overexpression (P = 0.005), and high postoperative carcinoembryonic antigen (CEA) levels (P = 0.001) were independent predictors of early failure. Additionally, ERCC1 overexpression was not only a predictor of early failure but also for disease-free survival (P < 0.001) and overall survival (P < 0.001). However, no predictive roles of ERCC2 and XRCC1 expression among these analyzed patients.

CONCLUSIONS

ERCC1 overexpression is an important predictor of early failure in patients with stage III CRC administrating FOLFOX-4 adjuvant chemotherapy and this marker may help identify patients who would benefit from intensive follow-up and enhance therapeutic programs.