RESUMEN
Traditional otic drug delivery methods lack controlled release capabilities, making reverse gelatination gels a promising alternative. Reverse gelatination gels are colloidal systems that transition from a sol to a gel phase at the target site, providing controlled drug release over an extended period. Thermosensitive norfloxacin reverse gelatination gels were developed using a Quality by Design (QbD)-based optimization approach. The formulations were evaluated for their in vitro release profile, rheological behavior, visual appearance, pH, gelling time, and sol-gel transition temperature. The results show that the gelation temperatures of the formulations ranged from 33 to 37 °C, with gelling durations between 35 and 90 s. The drug content in the formulations was uniform, with entrapment efficiency ranging from 55% to 95%. Among the formulations, F10 exhibited the most favorable properties and was selected for a stability study lasting 60 days. Ex-vivo release data demonstrate that the F10 formulation achieved 95.6percentage of drug release at 360 min. This study successfully developed thermosensitive norfloxacin reverse gelatination gels using a QbD-based optimization approach. The selected formulation, F10, exhibited desirable properties in terms of gelling temperature, drug content, and release profile. These gels hold potential for the controlled delivery of norfloxacin in the treatment of ear infections.
RESUMEN
The aim of the present study was to review the streptozotocin-nicotinamide (STZ-NA) diabetes model. Type 2 diabetes is more prevalent (90-95%) in adults than type 1. Experimentally- induced diabetes models may be established by chemicals, viral agents, insulin antibodies, surgery, etc. The most advisable and prompt method to induce diabetes is using chemicals, and STZ and alloxan are widely used chemicals. STZ has proven to be a better diabetogenic agent than alloxan because alloxan has many drawbacks, as it induces only type 1 diabetes, has a high mortality rate in rats, and causes ketosis in animals. Moreover, it has lesser selectivity towards ß-cells, and the diabetes-induced is reversible. STZ can be used to induce both type 1 and type 2 diabetes. It is noted that the genotoxic behavior of STZ in animals is accomplished through a reduction of nicotinamide adenine dinucleotide (NAD+) in pancreatic ß-cells via the GLUT2 (Glucose transporter 2), which can cause cellular damage by DNA (Deoxyribonucleic acid) strand breaks that lead to cell death. NA is a biochemical precursor of NAD+, and it is a poly-ADP-ribose-polymerase-1 (PARP- 1) inhibitor. NAD+ is an important redox reaction co-enzyme for the production of adenosine triphosphate (ATP) and many other metabolic pathways. Extreme DNA damage contributes to the over-activation of PARP-1, loss of cellular resources, and necrotic cells death. Some studies have expressed that NA can protect pancreatic ß-cells against the severe cytotoxicity of STZ. The review concluded that the STZ-NA model is dependent on the competency of NA to attain partial protection against the ß-cytotoxic essence of STZ to induce type-2 diabetes.