Tetrahydrocurcumin mitigates acute hypobaric hypoxia-induced cerebral oedema and inflammation through the NF-κB/VEGF/MMP-9 pathway.

High-altitude cerebral oedema (HACE) is a potentially fatal manifestation of high-altitude sickness and is caused partly by inflammation and the blood-brain barrier disruption. Tetrahydrocurcumin (THC) has been reported to exert effective antioxidative and anti-inflammatory effects; This study sought to elucidate the underlying mechanism of THC in mitigating HACE using a mouse model. Our results revealed that prophylactic administration of THC (40 mg/kg) for 3 days significantly alleviated the increase in brain water content (BWC), interleukin-1ß (IL-1ß) and TNF-α levels caused by acute hypobaric hypoxia (AHH). Additionally, superoxide dismutase (SOD) activity was increased by THC to enhance the ability to resist hypoxia. Histological and ultrastructural analysis of the cerebrum revealed that THC administration mitigated AHH-induced pericellular oedema and reduced the perivascular space, resulting in the simultaneous remission of oedema and protection of mitochondria in the cerebrum. In vitro, astrocytes exposed to hypoxia (4% O2 ) for 24 hr exhibited and increase in IL-1ß expression followed by an increase in vascular endothelial growth factor (VEGF) levels. Furthermore, THC administration remarkably downregulated VEGF, matrix metallopeptidase-9 (MMP-9), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) expression, both in vivo and in vitro. Our data highlight the potential prophylactic activity of THC in HACE, it effectively mitigates AHH-induced cerebral oedema and inflammation is associated with the inhibition of the NF-κB/ VEGF/MMP-9 pathways.

Tetrahydrocurcumin Ameliorates Acute Hypobaric Hypoxia-Induced Cognitive Impairment in Mice.

Ma, Xuexinyu, Yang Pan, Yuye Xue, Yao Li, Yan Zhang, Yani Zhao, Xingzhao Xiong, Jianbo Wang, and Zhifu Yang. Tetrahydrocurcumin ameliorates acute hypobaric hypoxia-induced cognitive impairment in mice. High Alt Med Biol. 23:264-272, 2022. Background: Hypobaric hypoxia (HH) impairs spatial learning and increases oxidative stress in rodents. We hypothesized that tetrahydrocurcumin (THC) may attenuate HH-induced neurobehavioral deficits by reducing HH-induced lipid peroxidation and increasing glycolytic activity. Materials and Methods: A C57BL/6 mouse model of acute high altitude brain injury was established using an animal decompression chamber for 24 hours. Cognitive and behavioral assessments were conducted using the Y-maze, open field, and Rotarod tests. We measured superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity; malondialdehyde (MDA) and reactive oxygen species levels; anti-neuronal core antigen (NeuN) immunoreactivity; and active occludin, hypoxia-inducible factor-1α, glucose transporter 1 (GLUT1), and GLUT3 expression levels in mice brain tissue. Results: The mice in the THC group showed improved cognitive impairment compared with those in the HH group in cognitive and behavioral tests, but failed to show improvement in the decline in coordination. The mice in the THC group were more effected than those in the HH group in demonstrating alleviation of hyperemia in cortical vessels and cell voids, and cells in the CA1 region were more closely arranged. Compared with those in the mice of the HH group, the concentration of MDA decreased significantly, the expression of occludin, NeuN immunoreactivity, and the activities of SOD and GSH-Px significantly increased in the mice of the THC group. An increase in GLUT1 expression was observed in HH-exposed animals (N group vs. HH group: 0.4 ± 0.08 vs. 0.60 ± 0.07, p < 0.05), and this increase was enhanced in animals treated with THC (HH group vs. THC group: 0.60 ± 0.07 vs. 0.82 ± 0.08, p < 0.05). Conclusions: THC improved cognitive impairment in mice, accompanied by reduced oxidative stress and increased GLUT1 protein levels.

Yohimbine hydrochloride inhibits benign prostatic hyperplasia by downregulating steroid 5α-reductase type 2.

Benign prostatic hyperplasia (BPH) is a frequently encountered disease in older men that affects sexual function and is capable of causing lower urinary tract dysfunction. Unfortunately, current treatment options for BPH primarily seek to address the lower urinary tract dysfunction aspect of the disease and do not improve sexual function. Yohimbine has been effectively used for decades to treat erectile dysfunction. Therefore, the objective of this study was to evaluate the inhibitory effect of yohimbine on BPH and explore the associated underlying mechanisms. Thirty-six rats were randomly divided into the control, BPH, finasteride (1 mg/kg), and yohimbine (2, 4, and 8 mg/kg) groups. Except for the rats in the control group, those in the other groups were subcutaneously injected testosterone propionate (5 mg/kg/day) daily for a period of 4 weeks to establish BPH models. They were also administration the corresponding drug daily for a period of 6 weeks. After the treatments, in addition to determining prostate wet weight and index, the histopathological status of the prostate was observed, and the levels of testosterone, dihydrotestosterone, prostatic acid phosphatase, the prostate-specific antigen, proliferating cell nuclear antigen, and steroid 5α-reductase were determined. Specifically, the administration of 2, 4, and 8 mg/kg yohimbine inhibited prostatic index increase by 46.7, 55.1, and 69.3%, respectively, in BHP rats. Further, yohimbine significantly reduced the levels of dihydrotestosterone, prostatic acid phosphatase, prostate-specific antigen, proliferating cell nuclear antigen, and steroid 5α-reductase, suggesting that it exerts beneficial effects against BPH by modulating the steroid 5α-reductase pathway.