Shuai Yan

Construction of naringenin-loaded chitosan/sodium alginate nanocomposite gels by sequential TPP and Ca ²⁺ ionic gelation, followed by gastric protection and sustained intestinal release.

Background: Slow transit constipation (STC) is a prevalent functional gastrointestinal disorder that significantly affects people's quality of life. Aurantii Fructus Immaturus (Zhishi, ZS) and Atractylodis Macrocephalae Rhizoma (Baizhu, BZ) are a classic herbal pair in traditional Chinese medicine (TCM) for regulating spleen‐stomach function, respectively recognized for their properties of “replenishing qi and fortifying the spleen” and “dispersing stagnation and promoting digestion”. This study aimed to elucidate the mechanisms by which ZSBZ ameliorates STC through regulating mitophagy in ICCs and restructuring gut microbiota composition. Methods: A rat model of STC was established by oral gavage administration of loperamide hydrochloride (3 mg/kg·day). The therapeutic effects of ZSBZ were evaluated by assessing rat body weight, 6‐h fecal number, fecal water content, and intestinal transit rate. Histopathological changes in the colon were observed using hematoxylin–eosin (HE) staining and Alcian blue‐periodic acid Schiff (AB‐PAS) staining. The ultrastructure of colon tissues was observed by transmission electron microscopy (TEM). Immunohistochemistry (IHC) was used to detect the expression of c‐Kit, SCF, and autophagy‐related markers (p62, Beclin1, and LC3II/I) in colon tissues. The expression levels of α‐KGDHC and PDH were measured by ELISA. Combined with biochemical assays for SOD, MDA, respiratory chain complexes I and II, and ATP levels, a comprehensive assessment of cellular mitochondrial oxidative stress status and energy metabolism function was performed. Flow cytometry was used to quantify intracellular Ca ²⁺ concentration and mitochondrial membrane potential (MMP) in cells isolated from colonic tissues. Mitophagy‐related protein and mRNA expression were analyzed by Western blotting and reverse transcription quantitative polymerase chain reaction (RT‐qPCR). Apoptosis in rat colonic tissues was detected using TUNEL assay. Gut microbiota composition was analyzed by 16S rRNA gene sequencing, and its metabolic functional potential was predicted. Results: Our results showed that ZSBZ significantly ameliorated defecation function and enhanced intestinal motility in a rat model of STC. Histopathological and ultrastructural analyses revealed that ZSBZ effectively restored colonic mucosal damage, increased goblet cell numbers, and attenuated mitochondrial swelling with cristae disruption in ICCs of STC rats. Meanwhile, ZSBZ improved mitochondrial dysfunction by reducing MDA levels and increasing SOD activity in colonic tissues. Furthermore, ZSBZ improved mitochondrial energy metabolism by increasing ATP content, restoring respiratory chain complex I and II activities, and elevating α‐KGDHC and PDH activities, thereby reversing the decline in mitochondrial membrane potential and the increase in intracellular Ca ²⁺ concentration in cells isolated from colonic tissues. Mechanistically, ZSBZ attenuated excessive mitophagy in colonic ICCs by downregulating autophagy‐related genes and proteins, restoring p62 expression, and suppressing the elevated mRNA and protein expression of the mitophagy‐related markers PINK1 and Parkin. In addition, 16S rRNA gene sequencing demonstrated that ZSBZ reshaped the gut microbiota in STC rats, characterized by a decreased abundance of Proteobacteria and an increased abundance of Bacteroidota . KEGG functional prediction further indicated that ZSBZ regulated mitochondrial metabolism‐related pathways, possibly contributing to the amelioration of colonic dysmotility. Conclusion: ZSBZ significantly alleviated constipation symptoms in STC rats. The mechanism may involve inhibition of excessive mitophagy in ICCs and restructuring of gut microbiota composition. This study provides compelling theoretical support for ZSBZ as a therapeutic strategy against STC and offers novel insights into intestinal motility restoration in humans.

Ti ₃ C ₂ T _x MXene–AuPtPdCu nanoalloy-based aptameric electrochemical immunosensor enables ultrasensitive detection of colorectal cancer-derived exosomes via CD63 recognition and DPV signal suppression, offering a promising liquid-biopsy platform.

An advanced polymeric system was developed to overcome the limitations of poor solubility and bioavailability associated with baicalin, a natural flavonoid glycoside derived from Scutellaria baicalensis, by employing an emulsification–solvent diffusion method to formulate a novel drug delivery vehicle. The optimized formulation exhibited a uniform mean particle size of 158 ± 12 nm, a narrow polydispersity index (PDI) of 0.21, and a zeta potential of –18 ± 3 mV, ensuring stable dispersion. High encapsulation efficiency was achieved, reaching up to 92% across multiple batches. In vitro release studies demonstrated a pH-responsive behavior; approximately 35% of the drug was released in simulated gastric fluid (SGF) (pH 1.2) and nearly 70% in simulated intestinal/colonic fluid (pH 6.8–7.4) within 24 h. Kinetic analysis revealed that the Korsmeyer–Peppas model provided the best fit to the release data, indicating a diffusion-controlled release under acidic conditions and a combination of diffusion and polymer relaxation mechanisms at neutral pH, supporting controlled and sustained release behavior. Cellular internalization experiments confirmed dose-dependent uptake, with maximum uptake rates of 62% in HCT116 and 58% in HT29 cells, while cytotoxicity assays revealed significantly lower IC50 values (12 μg/mL in HCT116 and 15 μg/mL in HT29) compared to free drug formulations (20 μg/mL and 25 μg/mL, respectively). Furthermore, flow cytometry analysis showed a marked increase in apoptotic populations, with Sub-G1 fractions rising from 5.2% to 24.8% and overall apoptotic rates reaching 38% post-treatment. These findings suggest that the engineered delivery system provides enhanced therapeutic efficacy through improved bioavailability, targeted cellular uptake, and effective induction of apoptosis for advanced treatment strategies. Overall, the results underscore the significance of material engineering in optimizing physicochemical properties and therapeutic outcomes for improved efficacy. This innovative platform demonstrates strong potential for future comprehensive preclinical investigations, which are necessary to further assess its safety and efficacy before considering clinical applications.

Background: Slow-transit constipation (STC) is a widespread functional gastrointestinal condition distinguished by decreased colonic motility as an essential clinical characteristic. The excessive autophagy of interstitial cells of Cajal (ICCs) causes phenotypic changes and functional abnormalities, which are important in colonic dysmotility. Naringenin (NAR) has been shown to regulate gastrointestinal motility disorders. The present study aimed to elucidate the regulatory role of naringenin in autophagy in STC and its underlying mechanism.Methods: In vitro, ICCs were stimulated with L-glutamic acid (GA) to induce autophagy and treated with NAR. A CCK8 assay was performed to evaluate the cytotoxic effect of NAR. Annexin V-FITC/PI staining was used to examine NAR apoptosis. The expression of the autophagy markers Beclin1 and LC3B, as well as proteins related to the AMPK/mTOR/ULK1 pathway was investigated through quantitative PCR, Western blot analysis and immunofluorescence staining. The small interfering RNA (siRNA) technique was used to knockdown selective autophagy receptors (NDP52, OPTN, NBR1, and p62) in ICCs. Coimmunoprecipitation (co-IP) was used to evaluate the binding of pS757-ULK1 to the autophagy receptors NDP52 and OPTN in ICCs. Immunofluorescence (IF) staining was performed to observe the colocalization of pS757-ULK1 with exogenous NDP52 and OPTN in ICCs. In vivo, male C57BL/6 mice were administered loperamide (10 mg/kg) to establish a constipation model and then treated with NAR (75/150/300 mg/kg) for 2 weeks. Finally, colonic tissues were collected for a histological analysis and immunohistochemical for cell growth factor receptor kit (c-Kit) and anoctamin-1 (ANO1).Results: Our results indicated that NAR improved the survival and apoptosis of ICCs after GA by inhibiting autophagy through the partial suppression of the AMPK/mTOR/ULK1 signalling pathway. Moreover, NAR inhibited the autophagic degradation of pS757-ULK1 by weakening the interactions between pS757-ULK1 and the selective autophagy receptor genes NDP52 and OPTN. Further research revealed that NAR could increase the moisture content of faeces; increase the rate of small intestinal propulsion in mice; increase the serum concentrations of excitatory neurotransmitters such as GAS, 5-HT, MTL, and SP; and increase the expression levels of ANO1 and c-Kit in the colon, and the molecular mechanism was consistent with the in vitro results.Conclusion: NAR attenuates the AMPK/mTOR/ULK1 pathway in ICCs, thereby improving STC colonic dysmotility and underscoring its promise as a therapeutic option for STC.

Adhesive intestinal obstruction (AIO) represents a common postoperative complication, particularly following abdominal surgery, with reported incidence rates varying between 50 and 80%. Traditional Chinese Medicine (TCM) has proven clinically effective in managing AIO, offering diverse therapeutic approaches that facilitate multi-pathway and multi-target treatment. Clinical evidence consistently supports the favorable safety profile of Traditional Chinese Medicine (TCM). Nevertheless, several critical challenges remain to be addressed, including its complex multi-component nature, insufficiently elucidated mechanisms of action, lack of precise dosage standards, inconsistencies in decoction preparation methods, inconvenient administration procedures, and a paucity of large-scale, multicenter clinical trials with robust evidence. These barriers hinder the widespread adoption and clinical integration of TCM. Moving forward, large-scale, multicenter studies are essential to further investigate the safety and efficacy of TCM. Moreover, reforms in its administration methods and deeper exploration of its mechanisms in AIO treatment are crucial.

Slow transit constipation (STC) is a complication of depression that can negatively impact patient prognosis and quality of life. Nonetheless, the pathogenesis of STC is unclear. In this work, colon tissues from STC and non-STC patients were utilized to determine transcriptome expression patterns (messenger ribonucleic acids [mRNAs], Long noncoding RNAs [lncRNAs], and Circular RNAs [circRNAs]) via high-throughput sequencing. We found that 4430 mRNAs, 984 lncRNAs, and 2152 circRNAs exhibited substantial variations in expression patterns in the colon tissues of STC and non-STC patients. Next, we constructed a protein-protein interaction network and identified three significant elements, namely, POLR2B, SRSF1, and SUMO1, which attracted our interest. Utilizing the data of 6 upregulated circRNAs and 10 downregulated circRNAs, we created a competing endogenous RNA network. Subsequently, we found that hsa_circ_0000994 and hsa_circ_0008699 were significantly enriched in the upregulated and downregulated networks, respectively. The coexpression network analysis suggested that circRNAs and lncRNAs might exert control over mRNAs by influencing the neural functions of STC. According to the results of the integrated circRNA-miRNA-mRNA network, circRNA-regulated mRNAs were linked to both the transforming growth factor-β (TGF-β) and Notch signaling pathways. Our findings could provide new perspectives for identifying potential prognostic markers in STC. Targeting SUMO1 may present a promising approach to address colonic motility disorders in STC therapy.