Hydrogen sulfide as an anti-calcification stratagem in human aortic valve: Altered biogenesis and mitochondrial metabolism of H2S lead to H2S deficiency in calcific aortic valve disease.

Hydrogen sulfide (H2S) was previously revealed to inhibit osteoblastic differentiation of valvular interstitial cells (VICs), a pathological feature in calcific aortic valve disease (CAVD). This study aimed to explore the metabolic control of H2S levels in human aortic valves. Lower levels of bioavailable H2S and higher levels of interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) were detected in aortic valves of CAVD patients compared to healthy individuals, accompanied by higher expression of cystathionine γ-lyase (CSE) and same expression of cystathionine ß-synthase (CBS). Increased biogenesis of H2S by CSE was found in the aortic valves of CAVD patients which is supported by increased production of lanthionine. In accordance, healthy human aortic VICs mimic human pathology under calcifying conditions, as elevated CSE expression is associated with low levels of H2S. The expression of mitochondrial enzymes involved in H2S catabolism including sulfide quinone oxidoreductase (SQR), the key enzyme in mitochondrial H2S oxidation, persulfide dioxygenase (ETHE1), sulfite oxidase (SO) and thiosulfate sulfurtransferase (TST) were up-regulated in calcific aortic valve tissues, and a similar expression pattern was observed in response to high phosphate levels in VICs. AP39, a mitochondria-targeting H2S donor, rescued VICs from an osteoblastic phenotype switch and reduced the expression of IL-1ß and TNF-α in VICs. Both pro-inflammatory cytokines aggravated calcification and osteoblastic differentiation of VICs derived from the calcific aortic valves. In contrast, IL-1ß and TNF-α provided an early and transient inhibition of VICs calcification and osteoblastic differentiation in healthy cells and that effect was lost as H2S levels decreased. The benefit was mediated via CSE induction and H2S generation. We conclude that decreased levels of bioavailable H2S in human calcific aortic valves result from an increased H2S metabolism that facilitates the development of CAVD. CSE/H2S represent a pathway that reverses the action of calcifying stimuli.

Simplification of the coma recovery scale-revised in disorders of consciousness: A prospective observational study.

The Coma Recovery Scale-Revised (CRS-R) is the gold standard behavioral assessment scale for diagnosis of patients with disorders of consciousness (DOC). The reliability of CRS-R in monitoring the state of consciousness is well established. It is widely used by experts working in the fields of DOC. However, it is complex, time-consuming and difficult to use by non-professionals. Hence, it is imperative to simplify the evaluation to ease clinical workflow and increase work efficiency. In this study we evaluated the accuracy of a simplified scale using only 8 most commonly observed behaviors from the standard 29-item CRS-R scale. To assess the diagnostic accuracy of the simplified evaluation process of CRS-R compared to the standard CRS-R, a total of 150 patients with DOC who were admitted to the Hospital of Zhejiang People's Armed Police between February 2020 and September 2021 were screened in a prospective, observational study. Two trained clinicians used the CRS-R and the simplified CRS-R to evaluate the consciousness level of the enrolled patients, respectively. SPSS 23 was used for statistical analysis. Weighted kappa was used to demonstrate the level of agreement between the two methods. A p-value < 0.01 was considered to be statistically significant. Kappa coefficient was 0.952 (95 % CI: 0.905-0.999, p < 0.01), which indicated that the difference was statistically significant, thereby suggesting satisfactory level of agreement between the diagnostic outcomes of the CRS-R and simplified CRS-R. The simplified CRS-R could determine the state of consciousness of patients with ease and high accuracy.

Eugenol restrains abdominal aortic aneurysm progression with down-regulations on NF-κB and COX-2.

Abdominal aortic aneurysm (AAA) is a lethal disease without available medicine for treatment. This study aimed to evaluate the efficiency of eugenol (4-allyl-2-methoxyphenol) against AAA and the underlying mechanism. Eugenol is the major bioactive component of clove. A mouse AAA model was established through porcine pancreatic elastase (PPE) incubation peri-adventitially and 1% 3-aminopropanonitrile (BAPN) diet. Continuous AAA progression from day 0 to day 15 was observed after PPE plus BAPN treatment, according to the AAA diameter and histopathological evaluation. Accompanying with AAA progression, sustained increased expressions of CD68, COX-2 and NF-κB were observed through immunofluorescence assay. After elucidation the efficiency of eugenol against AAA progression by AAA diameter, hematoxylin-eosin staining and orcein staining, the down-regulations of eugenol on COX-2 and NF-κB were further detected by immunohistochemistry and western blot. Eugenol not only blocked AAA expansion and protected the integrity of aortic structure in a dose-dependent manner, but also held high oral bioavailability. Excellent efficiency, high oral bioavailability and down-regulation on COX-2/NF-κB endowed eugenol great potential for future AAA therapy.

Progression and Regression of Abdominal Aortic Aneurysms in Mice.

OBJECTIVE: Abdominal aortic aneurysm (AAA) is a significant medical problem with a high mortality rate. Nevertheless, the underlying mechanism for the progression and regression of AAA is unknown. METHODS: Experimental model of AAA was first created by porcine pancreatic elastase incubation around the infrarenal aorta of C57BL/6 mice. Then, AAA progression and regression were evaluated based on the diameter and volume of AAA. The aortas were harvested for hematoxylin-eosin staining (HE), orcein staining, sirius red staining, immunofluorescence analysis and perls' prussian blue staining at the indicated time point. Finally, ß-aminopropionitrile monofumarate (BAPN) was used to explore the underlying mechanism of the regression of AAA. RESULTS: When we extended the observation period to 100 days, we not only observed an increase in the AAA diameter and volume in the early stage, but also a decrease in the late stage. Consistent with AAA diameter and volume, the aortic thickness showed the same tendency based on HE staining. The elastin and collagen content first degraded and then regenerated, which corresponds to the early deterioration and late regression of AAA. Then, endogenous up-regulation of lysyl oxidase (LOX) was detected, accompanying the regression of AAA, as detected by an immunofluorescent assay. BAPN and LOX inhibitor considerably inhibited the regression of AAA, paralleling the degradation of elastin lamella and collagen. CONCLUSION: Taken together, we tentatively conclude that endogenous re-generation of LOX played an influential role in the regression of AAA. Therefore, regulatory factors on the generation of LOX exhibit promising therapeutic potential against AAA.