Catalpol relieved angiotensin II-induced blood-brain barrier destruction via inhibiting the TLR4 pathway in brain endothelial cells.

CONTEXT: Catalpol is a major bioactive constituent of Rehmannia glutinosa Libosch (Scrophulariaceae), a traditional Chinese medicine, which is widely used in multiple diseases, including hypertension. OBJECTIVES: To explore whether catalpol protects against angiotensin II (Ang II)-triggered blood-brain barrier (BBB) leakage. MATERIALS AND METHODS: The bEnd.3 cells and BBB models were pre-treated with or without catalpol (50, 200 and 500 µM) or TAK-242 (1 µM) for 2 h and then with Ang II (0.1 µM) or LPS (1 µg/mL) for 24 h. Cell viability was determined by the MTT assay. The levels of Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), inducible nitric oxide synthase (iNOS), tumour necrosis factor-α (TNF-α), caveolin-1 (Cav-1) and p-eNOS/eNOS were tested by western blot. The BBB permeability was evaluated by the flux of bovine serum albumin-fluorescein isothiocyanate (BSA-FITC) across monolayers. nuclear factor kappa-B (NF-κB) p65 nuclear translocation was explored by immunofluorescence staining. RESULTS: Ang II (0.1 µM) decreased the cell viability to 86.52 ± 1.79%, elevated the levels of TLR4, MyD88, iNOS, TNF-α and Cav-1 respectively to 3.7-, 1.5-, 2.3-, 2.2- and 2.7-fold, reduced the level of p-eNOS/eNOS to 1.6-fold in bEnd.3 cells, and eventually increased BBB permeability. Catalpol dose-dependently reversed these changes at 50-500 µM. Meanwhile, catalpol (500 µM) inhibited the upregulated levels of TLR4 pathway-related proteins and NF-κB p65 nuclear translocation, decreased the enhanced transcytosis, and relieved the BBB disruption caused by both LPS (the TLR4 activator) and Ang II. The effects are same as TAK-242 (the TLR4 inhibitor). CONCLUSIONS: Catalpol relieved the Ang II-induced BBB damage, which indicated catalpol has high potential for the treatment of hypertension-induced cerebral small vessel disease (cSVD).

The protective effect of harpagoside on angiotensin II (Ang II)-induced blood-brain barrier leakage in vitro.

Hypertension and its associated dysfunction of the blood-brain barrier (BBB) contribute to cerebral small vessel disease (cSVD). Angiotensin II (Ang II), a vasoactive peptide of the renin-angiotensin system (RAS), is not only a pivotal molecular signal in hypertension but also causes BBB leakage, cSVD, and cognitive impair. Harpagoside, the major bioactive constituent of Scrophulariae Radix, has been commonly used for the treatment of multiple diseases including hypertension in China. The effect of harpagoside on Ang II-induced BBB damage is unclear. We employed an immortalized endothelial cell line (bEnd.3) to mimic a BBB monolayer model in vitro and investigated the effect of harpagoside on BBB and found that harpagoside alleviated Ang II-induced BBB destruction, inhibited Ang II-associated cytotoxicity in a concentration-dependent manner and attenuated Ang II-induced reactive oxygen species (ROS) impair by downregulation of Nox2, Nox4, and COX-2. Harpagoside prevented Ang II-induced apoptosis via keeping Bax/Bcl-2 balance, decreasing cytochrome c release, and inactivation of caspase-8, caspase-9, and caspase-3 (the mitochondria-dependent and death receptor-mediated apoptosis pathways). Moreover, harpagoside can alleviate Ang II-induced BBB damage through upregulation of tight junction proteins and decrease of caveolae-mediated endocytosis. Thus, harpagoside might be a potential drug to treat Ang II-induced cSVD.

Effect of micronutrient pack on micronutrient status and antioxidant capacities among institutional older adults in Shanghai, China.

BACKGROUND AND OBJECTIVES: Older adults are at increased risk of micronutrient deficiency, disrupting the balance of oxidation/antioxidation system and leading to serious health burdens. This study aimed to investigate the effect of micronutrient pack on micronutrient status and oxidative/antioxidative biomarkers in institutional older adults. METHODS AND STUDY DESIGN: Subjects aged 65-100 years were randomly assigned to either intervention group or control group (n=49 each), providing a package of micronutrient pack or placebo daily for three months. The concentrations of micronutrients, malondialdehyde (MDA), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) were detected both at baseline and at the end of the study. RESULTS: The changes in concentrations of serum folate (21.1±1.6 vs 0.6±0.5 nmol/L), vitamin B-1 (3.4±0.4 vs -0.2±0.3 nmol/L), vitamin B-2 (11.5±3.3 vs 2.3±1.4 nmol/L), vitamin B-12 (128.8±34.8 vs 13.3±16.0 pmol/L), 25-hydroxyvitamin D (17.8±1.3 vs -0.8±0.5 ng/mL) and plasma zinc (0.6±1.8 vs -9.6±1.9 µmol/L) over 3-months were significantly increased in the intervention group compared with the control group (all p<0.05). While the prevalence of folate, vitamin B-12 and vitamin D deficiencies were significantly decreased after 3-months intervention (all p<0.05). Moreover, changes in serum MDA level (-1.5±0.2 vs 0.2±0.3 nmol/mL) were remarkably reduced, and the activities of serum GSH-Px (1.3±0.3 vs 0.3±0.2 ng/mL) and plasma SOD (14.3±2.4 vs -2.1±2.4 U/mL) were increased in the intervention group than those of in the control group (all p<0.01). CONCLUSIONS: The micronutrient pack among institutional older adults was well-accepted with good compliance and tolerance. The 3-month intervention may improve micronutrient status and enhance antioxidative capacities.