Borneol promotes autophagic degradation of HIF-1α and enhances chemotherapy sensitivity in malignant glioma.

Background: Gliomas are characterized by high mortality rates and resistance. Even with conventional chemotherapy the prognosis of glioblastoma remains poor. Many medications are not optimally effective due to limited bioavailability. The bioavailability of medicine can be enhanced by borneol, a monoterpenoid substance. In this study, we investigated the effect of borneol, a commonly used Chinese medicine, on chemosensitivity in C6 glioma and U251 human glioma cell lines and elucidated its therapeutic molecular targets. Methods: The chemosensitivity-inducing effects of borneol in C6 and U251 cells were examined using CCK8 and clonal formation assays. The mechanism underlying the effect of borneol was evaluated through immunohistochemistry and western blotting assays. Further, the number of autophagosomes was determined via transmission electron microscopy. Finally, the chemical sensitization effect of borneol was evaluated in SD rats after C6 orthotopic tumor transplantation. Results: Borneol increased cytotoxicity in C6 and U251 cells in response to temozolomide (TMZ). In addition, through transmission electron microscopy, western blotting, and immunohistochemical tests, we found that borneol combined with TMZ significantly increased the level of autophagy and that hypoxia inducible factor-1(HIF-1α) is a candidate target through which borneol enhances the cytotoxic effect of TMZ. Borneol's ability to enhance HIF-1α degradation was counteracted following the administration of autophagy inhibitors. In vivo, borneol treatment was found to enhance the anticancer effect of TMZ and delay tumor progression, and this effect was closely related to its ability to promote the autophagic degradation of HIF-1α. Conclusions: HIF-1α might be a valid therapeutic target of borneol, which can be potentially applied as a chemosensitizing drug used for glioma treatment.

Peripheral Blood Th1/Th17 Immune Cell Shift is Associated with Disease Activity and Severity of AQP4 Antibody Sero-Positive Neuromyelitis Optica Spectrum Disorder.

Purpose: Neuromyelitis optica spectrum disorder (NMOSD) is a rare recurrent autoimmune disease of the central nervous system. However, to date, the peripheral blood profile of the T helper cell subsets in NMOSD remains controversial and poorly understood. This study aimed to compare the levels of helper T cell subsets in the peripheral blood from patients with NMOSD in different phases of the disease and studied their correlation with the clinical severity of the disease. Patients and methods: We used flow cytometry with cellular membrane surface staining to measure the levels of helper T cell subsets in 50 patients with NMOSD during the attack (n = 25) and remission (n = 25) phases and in 21 healthy controls. Results: Patients with NMOSD had higher levels of Th1 and Th17 cells in the attack phase compared to parallel populations in the remission phase and healthy controls. Th1/Th2 and Th17/Treg ratios were positively correlated with the severity of the disease in the attack phase of NMOSD. In contrast, Treg cell levels were negatively correlated with the severity of the disease in the attack phase in patients with NMOSD. Conclusion: The peripheral blood immune profile in NMOSD towards a Th1/Th17 cell-mediated pro-inflammatory immune response, which is associated with disease activity and severity of neuromyelitis optica spectrum disorder.

Mechanism underlying linezolid-induced peripheral neuropathy in multidrug-resistant tuberculosis.

Multidrug-resistant tuberculosis (MDR-TB) remains a main global health concern as there is no comprehensive therapeutic intervention yet and numerous adverse effects follow the therapeutic process. In recent years, linezolid has been frequently used for treating MDR-TB. However, peripheral neuropathy associated with linezolid has reduced patient compliance. The current study explored the mechanism underlying linezolid-induced peripheral neuropathy in MDR-TB. Autophagy plays a neuroprotective role against peripheral nerve injury. We hypothesized that autophagy might also play a neuroprotective role against linezolid-induced peripheral neuropathy. In this study, we collected 12 questionnaires from MDR-TB patients in our hospital, and 10 of them developed linezolid-induced pain. The pain is mainly concentrated in the feet and accompanied by numbness. Subsequently, we used Sprague-Dawley (SD) rats and Schwann cells (SCs) to explore the mechanism. We found that linezolid causes a sparse arrangement of sciatic nerve tissue with associated loss of neurons, myelin sheaths, and down-regulation of LC3B expression. These results were also confirmed by in vitro experiments, showing that linezolid inhibited the proliferation of SCs. And the expression of P-AKT and P62 was elevated, and the expression of LC3B declined compared with the control group. Moreover, chloroquine (CQ), an autophagy inhibitor, also exhibited experimental results similar to linezolid. In summary, we conclude that linezolid-induced peripheral neuropathy is associated with the inhibition of autophagy flux.