Introduction: Asthma is a chronic airway inflammatory disease characterized by variable airflow limitation and intermittent symptoms. In well-controlled asthma, auscultation and spirometry often appear normal, making diagnosis challenging. Moreover, bronchial provocation tests carry a risk of inducing acute bronchoconstriction. This study aimed to develop a non-invasive, objective, and reproducible diagnostic method using machine learning-based lung sound analysis for the early detection of asthma, even during stable periods. Methods: We designed a machine learning algorithm to classify controlled asthma patients and healthy individuals using respiratory sounds recorded with a digital stethoscope. We enrolled 120 participants (60 asthmatic, 60 healthy). Controlled asthma was defined according to Global Initiative for Asthma (GINA) criteria and was supported by normal spirometry, no pathological auscultation findings, and no exacerbations in the past three months. A total of 3600 respiratory sound segments (each 3 s long) were obtained by dividing 90 s recordings from 120 participants (60 asthmatic, 60 healthy) into non-overlapping clips. The samples were analyzed using Mel-Frequency Cepstral Coefficients (MFCCs) and Tunable Q-Factor Wavelet Transform (TQWT). Significant features selected with ReliefF were used to train Quadratic Support Vector Machine (SVM) and Narrow Neural Network (NNN) models. Results: In 120 participants, pulmonary function test (PFT) results in the asthma group showed lower FEV1 (86.9 ± 5.7%) and FEV1/FVC ratios (86.1 ± 8.8%) compared to controls, but remained within normal ranges. Quadratic SVM achieved 99.86% accuracy, correctly classifying 99.44% of controls and 99.89% of asthma cases. Narrow Neural Network achieved 99.63% accuracy. Sensitivity, specificity, and F1-scores exceeded 99%. Conclusion: This machine learning-based algorithm provides accurate asthma diagnosis, even in patients with normal spirometry and clinical findings, offering a non-invasive and efficient diagnostic tool.

Background: Hypoxia induces pulmonary inflammation, oxidative stress and lung injury. Orientin has potent antioxidant and anti-inflammatory effects. This study evaluated the protective effects of orientin-loaded chitosan nanoparticles (CNP–Orientin) against hypoxia-induced lung injury in rats. Methods: A total of 48 female Sprague Dawley rats were exposed to intermittent hypoxia (7% O₂, 8 h/day for 7days) and assigned to normoxic or hypoxic groups. Hypoxic animals received no treatment, orientin alone, chitosan nanoparticles alone or CNP–Orientin, while normoxic rats served as controls. Lung tissues and blood samples were collected for assessment of oxidative stress markers, inflammatory and hypoxia-related signalling pathways, apoptosis-related gene expression, radiological evaluation, and histopathological scoring of lung injury and fibrosis. Results: Intermittent hypoxia increased pulmonary HIF-1α and iNOS levels, disrupted oxidative stress balance, elevated pro-inflammatory cytokines, enhanced apoptotic signalling, and induced histopathological lung injury compared with normoxic controls (p<0.05). Orientin or chitosan nanoparticles alone partially attenuated hypoxia-related alterations. Combined CNP–Orientin therapy resulted in greater reductions in oxidative stress, inflammatory signalling, and apoptotic markers compared with hypoxia alone and monotherapy groups (p<0.05). NF-κB and TNF-α expression, caspase-3 levels, antioxidant markers, and Bcl-2 expression differed among hypoxic groups. Histopathological lung injury and Modified Ashcroft fibrosis scores were lower in the CNP–Orientin group (p<0.001). Conclusion: CNP–Orientin attenuates hypoxia-induced pulmonary inflammation, oxidative stress, apoptosis, and early fibrosis, supporting its translational potential.

Background: Hypoxia triggers pulmonary inflammation and oxidative stress, leading to endothelial dysfunction, apoptosis and lung injury. Although the flavonoid orientin exhibits potent antioxidant and anti-inflammatory properties, its pharmacokinetic behavior remains incompletely characterized. Nanoparticle-based delivery systems may enhance efficacy. This study investigated whether Orientin delivered via chitosan nanoparticles (CNP–orientin) protects against hypoxia-induced pulmonary inflammation, oxidative stress, and tissue injury in rats. Methods: A total of 48 female Sprague–Dawley rats were randomized into four normoxic and four hypoxic groups (n = 6 per group). Rats in the hypoxic groups were exposed to intermittent hypoxia (7% O₂, 8 h/day for 7 days). Hypoxic rats were allocated to experimental groups, including an untreated hypoxia group and groups receiving orientin alone, chitosan nanoparticles alone or orientin-loaded chitosan nanoparticles (CNP–orientin), while normoxic rats served as controls. Hypoxic exposure was conducted using a controlled glove box system. At the end of the protocol, blood samples were collected for serum inflammatory marker analysis, and lung tissues were harvested to assess oxidative stress parameters, hypoxia- and inflammation-related signaling pathways, apoptosis-related gene expression, and histopathological lung injury and fibrosis. Results: Intermittent hypoxia significantly increased pulmonary HIF-1α and iNOS expression, oxidative stress markers (increased malondialdehyde and decreased superoxide dismutase and glutathione), pro-inflammatory cytokines (TNF-α, IL-1β), apoptotic signaling and histopathological lung injury compared with normoxic controls (p < 0.05). Treatment with orientin or chitosan nanoparticles alone attenuated hypoxia-associated biochemical and molecular alterations compared to untreated hypoxic rats (p < 0.05). Notably, CNP–orientin treatment significantly attenuated multiple oxidative stress, inflammatory, and apoptosis-related alterations compared with untreated hypoxic rats (p < 0.05). These protective effects were observed despite the substantially lower orientin-equivalent dose in the CNP–orientin formulation compared with free orientin. NF-κB and TNF-α expression, caspase-3 levels, antioxidant markers, and Bcl-2 expression differed significantly among hypoxic groups (p < 0.05). Histopathological lung injury and Modified Ashcroft fibrosis scores were significantly lower in the CNP–orientin group than in the untreated hypoxic group (p < 0.01 and p < 0.001, respectively). Conclusions: Orientin-loaded chitosan nanoparticles effectively mitigate hypoxia-induced pulmonary inflammation, oxidative stress, apoptosis and fibrotic injury. These findings identify CNP–orientin as a promising nanotherapeutic strategy for hypoxia-associated lung diseases and support further translational investigations.

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