Correction to "Rapamycin Inhibits Osteoclastogenesis and Prevents LPS-Induced Alveolar Bone Loss by Oxidative Stress Suppression".

[This corrects the article DOI: 10.1021/acsomega.3c01289.].

Rapamycin Inhibits Osteoclastogenesis and Prevents LPS-Induced Alveolar Bone Loss by Oxidative Stress Suppression.

Periodontitis is a progressive inflammatory skeletal disease characterized by periodontal tissue destruction, alveolar bone resorption, and tooth loss. Chronic inflammatory response and excessive osteoclastogenesis play essential roles in periodontitis progression. Unfortunately, the pathogenesis that contributes to periodontitis remains unclear. As a specific inhibitor of the mTOR (mammalian/mechanistic target of rapamycin) signaling pathway and the most common autophagy activator, rapamycin plays a vital role in regulating various cellular processes. The present study investigated the effects of rapamycin on osteoclast (OC) formation in vitro and its effects on the rat periodontitis model. The results showed that rapamycin inhibited OC formation in a dose-dependent manner by up-regulating the Nrf2/GCLC signaling pathway, thus suppressing the intracellular redox status, as measured by 2',7'-dichlorofluorescein diacetate and MitoSOX. In addition, rather than simply increasing the autophagosome formation, rapamycin increased the autophagy flux during OC formation. Importantly, the anti-oxidative effect of rapamycin was regulated by an increase in autophagy flux, which could be attenuated by blocking autophagy with bafilomycin A1. In line with the in vitro results, rapamycin treatment attenuated alveolar bone resorption in rats with lipopolysaccharide-induced periodontitis in a dose-dependent manner, as assessed by micro-computed tomography, hematoxylin-eosin staining, and tartrate-resistant acid phosphatase staining. Besides, high-dose rapamycin treatment could reduce the serum levels of proinflammatory factors and oxidative stress in periodontitis rats. In conclusion, this study expanded our understanding of rapamycin's role in OC formation and protection from inflammatory bone diseases.

[Effects of three Polyphenolic compounds on the intestinal flora of mice exposed simulated intermittent plateau hypoxia].

OBJECTIVE: To investigate the protective effects of three Polyphenolic compounds on intestinal microbial communities in mice exposed intermittent plateau hypoxia. METHODS: In this study, 60 healthy male Balb/c mice were randomly divided into plain control group, plateau control group, primary anthocyanin intervention group, quercetin intervention group and resveratrol intervention group, 12 mice in each group. Primary anthocyanin, quercetin and resveratrol were administrated by gavage at the doses of 50, 100 and 20 mg/kg in pharmacological intervention group, respectively. After exposure of the mice to simulation plateau-condition for 30 days, the serum samples were collected for DAO testing, sterile feces were collected in mice, and the diversity and genus level of the mouse gut bacteria were detected by using 16S rRNA technology. Ileum tissue was fixed and stained with HE. RESULTS: HE staining showed that the plateau control group had significant damage to the intestinal tissue structure compared to the plain control group, and the serum DAO concentration was increased (P＜0.05), but there was no statistical difference in the abundance and diversity of intestinal flora species. Contrast to simulated intermittent plateau hypoxia group, the structure of the intestine tissue and the level of DAO in the quercetin intervention group and resveratrol intervention group were improved(P＜0.05), the abundance and α diversity of the intestinal flora were decreased, the relative abundance of Bacteroidetes was reduced(P＜0.05), and the Firmicutes was increased. Concomitantly, significant decreases in relative abundance were observed for Corynebacterium glutamicum and Lactobacillus reuteri(P＜ 0.05). CONCLUSION: Quercetin and resveratrol showed some degree of protection to mice intestinal microbial communities, and increased the diversity and the abundance of the dominant flora and inhibited the growth of conditional pathogenic bacteria.

Isorhamnetin flavonoid synergistically enhances the anticancer activity and apoptosis induction by cis-platin and carboplatin in non-small cell lung carcinoma (NSCLC).

The development of novel antitumor drugs for the treatment of non-small cell lung carcinoma NSCLC is imperative in order to improve the efficacy of lung cancer therapy and prognosis. In the current study, we demonstrated the antitumor activity of isorhamnetin and its combinations with cisplatin and carboplatin against A-549 lung cancer cells. In order to assess the anticancer enhancing effect of isorhamnetin on cisplatin and carboplatin, A-549 cells were treated with isorhamnetin, cisplatin, carboplatin and their combinations and cell viability, cell apoptosis, cell cycle arrest as well as loss of mitochondrial membrane potential were evaluated by MTT assay, flow cytometry, confocal microscopy and fluorescence microscopy. The effect of the drugs on cancer cell migration, microtubule depolymerization as well activation of caspases was also studied. The results revealed that, as compared to single drug treatment, the combination of isorhamnetin with cisplatin and carboplatin resulted in greater effect in inhibiting cancer cell growth and inducing apoptosis. Combination of isorhamnetin with cisplatin and carboplatin resulted in more potent apoptosis induction as revealed by fluorescence microscopy using AO/PI double staining. Isorhamnetin and its combinations also triggered microtubule distortion and depolymerization. The combination of isorhamnetin with cisplatin and carboplatin increased the number of cells in G2/M phase dramatically as compared to single drug treatment. Moreover, isorhamnetin and its combinations with known anticancer drugs induced disruption of the mitochondrial membrane potential as well as activation of caspases 3, 9 and poly-(ADP-ribose) polymerase in A-549 cells. Isorhamnetin as well as its combinations with cisplatin and carboplatin resulted in inhibition of cancer cell migration significantly. Results of the current study suggest that isorhamnetin combinations with cisplatin and carboplatin might be a potential clinical chemotherapeutic approach for NSCLC.