Novel Stachydrine-Leonurine Conjugate SL06 as a Potent Neuroprotective Agent for Cerebral Ischemic Stroke

Stachydrine hydrochloride protects the ischemic heart by ameliorating endoplasmic reticulum stress through a SERCA2a dependent way and maintaining intracellular Ca2+ homeostasis

This study aimed to explore the effects and mechanism of action of stachydrine hydrochloride (Sta) against myocardial infarction (MI) through sarcoplasmic/endoplasmic reticulum stress-related injury. The targets of Sta against MI were screened using network pharmacology. C57BL/6 J mice after MI were treated with saline, Sta (6 or 12 mg kg-1) for 2 weeks, and adult mouse and neonatal rat cardiomyocytes (AMCMs and NRCMs) were incubated with Sta (10-4-10-6 M) under normoxia or hypoxia for 2 or 12 h, respectively. Echocardiography, Evans blue, and 2,3,5-triphenyltetrazolium chloride (TTC) staining were used for morphological and functional analyses. Endoplasmic reticulum stress (ERS), unfolded protein reaction (UPR), apoptosis signals, cardiomyocyte contraction, and Ca2+ flux were detected using transmission electron microscopy (TEM), western blotting, immunofluorescence, and sarcomere and Fluo-4 tracing. The ingredient-disease-pathway-target network revealed targets of Sta against MI were related to apoptosis, Ca2+ homeostasis and ERS. Both dosages of Sta improved heart function, decreased infarction size, and potentially increased the survival rate. Sta directly alleviated ERS and UPR and elicited less apoptosis in the border myocardium and hypoxic NRCMs. Furthermore, Sta upregulated sarcoplasmic reticulum Ca2+-ATPase 2a (SERCA2a) in both ischaemic hearts and hypoxic NRCMs, accompanied by restored sarcomere shortening, resting intracellular Ca2+, and Ca2+ reuptake time constants (Tau) in Sta-treated hypoxic ARCMs. However, 2,5-di-t-butyl-1,4-benzohydroquinone (BHQ) (25 μM), a specific SERCA inhibitor, totally abolished the beneficial effect of Sta in hypoxic cardiomyocytes. Sta protects the heart from MI by upregulating SERCA2a to maintain intracellular Ca2+ homeostasis, thus alleviating ERS-induced apoptosis.

Synthesis and Neuroprotective Evaluation of Substituted Indanone/Benzofuranone and Piperidine Hybrids

Based on the neuroprotection of butylphthalide and donepezil, a series of indanone/benzofuranone and piperidine hybrids were designed and synthesized for assessment of their neuroprotective activities, aiming to enhance the bioavailability and therapeutic efficacy of natural phthalide analogues. Within this study, it was observed that most indanone derivatives bearing 1-methylpiperidine in the tail segment demonstrated superior neuroprotective effects on the oxygen glucose deprivation/reperfusion (OGD/R)-induced rat primary neuronal cell injury model in vitro compared to benzofuranone compounds. Among the synthesized compounds, 11 (4, 14, 15, 22, 26, 35, 36, 37, 48, 49, and 52) displayed robust cell viabilities in the OGD/R model, along with favorable blood-brain barrier permeability as confirmed by the parallel artificial membrane permeability assay. Notably, compound 4 showed significant neuronal cell viabilities within the concentration range of 3.125 to 100 μM, without inducing cytotoxicity. Further results from in vivo middle cerebral artery occlusion/R experiments revealed that 4 effectively ameliorated ischemia-reperfusion injury, reducing the infarct volume to 18.45% at a dose of 40 mg/kg. This outcome suggested a superior neuroprotective effect compared to edaravone at 20 mg/kg, further highlighting the potential therapeutic efficacy of compound 4 in addressing neurological disorders.

Synthesis, characterization and anti-breast cancer activities of stachydrine derivatives

Stachydrine is a hydrophilic quaternary amine salt with good antitumor effect, but its application is limited due to its rapid metabolism and low bioavailability. We synthesized and evaluated nine prodrugs of stachydrine, which showed suitable hydrophobicity (CLogP: -2.58-4.78, vs SS-0: -3.32) and better in vitro anticancer activity (IC50: 0.34 μM-14.03 mM, vs SS-0: 38.97 mM-147.19 mM) in comparison with stachydrine. Among them, SS-12, SS-16 and SS-18 are the most effective compounds against 4T1 cells, and the IC50 is 2.15-24.14 μM. Especially, compared with stachydrine, SS-12 significantly blocked the cell cycle in the G0/G1 phase, reduced the mitochondrial membrane potential, and induced the apoptosis of 4T1 cells through mitochondria pathway, which increased the expressions of Bax and cleaved caspase-3 protein, decrease the expression of Bcl-2. The pharmacokinetics of SS-12 showed a rational bioavailability (79.6%), and a longer retention time (T1/2 = 7.62 h) than that of stachydrine (T1/2 ≈ 1.16 h) in rats. Compared with stachydrine, SS-12 significantly enhanced the anticancer efficacy (56.32% of tumor-inhibition rates, vs SS-0: 3.89%), meanwhile, ameliorated the tumor-induced organ damage in mice. Therefore, SS-12 may be a promising prodrug of stachydrine against breast cancer.

The eNOS-induced leonurine's new role in improving the survival of random skin flap

In reconstructive and plastic surgery, random skin flaps are commonly utilized to treat skin abnormalities produced by a variety of factors. Flap delay procedure is commonly used to reduce flap necrosis. Due to the limitations of various conditions, the traditional surgical improvement can't effectively alleviate the skin flap necrosis. And leonurine (Leo) has antioxidant and anti-inflammatory effects. In this study, we researched the mechanism underlying the influences of varied Leo concentrations on the survival rate of random skin flaps. Our results showed that after Leo treatment, tissue edema and necrosis of the flap were significantly reduced, while angiogenesis and flap perfusion were significantly increased. Through immunohistochemistry and Western blot, we proved that Leo treatment can upregulate the level of angiogenesis, while Leo treatment significantly reduced the expression levels of oxidative stress, apoptosis and inflammation. As a result, it can significantly improve the overall viability of the random skin flaps through the increase of angiogenesis, restriction of inflammation, attenuation of oxidative stress, and reduction of apoptosis. And this protective function was inhibited by LY294002 (a broad-spectrum inhibitor of PI3K) and L-NAME (NG- nitro-L-arginine methyl ester, a non-selective NOS inhibitor). All in all, Leo is an effective drug that can activate the eNOS via the PI3K/Akt pathway. By encouraging angiogenesis, preventing inflammation, minimizing oxidative stress, and lowering apoptosis, Leo can raise the survival rate of random skin flaps. The recommended concentration of Leo in this study was 30 mg/kg.

Stachydrine Relieved the Inflammation and Promoted the Autophagy in Diabetes Retinopathy Through Activating the AMPK/SIRT1 Signaling Pathway

Background

Diabetes retinopathy (DR) is a chronic, progressive, and potentially harmful retinal disease associated with persistent hyperglycemia. Autophagy is a lysosome-dependent degradation pathway that widely exists in eukaryotic cells, which has recently been demonstrated to participate in the DR development. Stachydrine (STA) is a water-soluble alkaloid extracted from Leonurus heterophyllus. This study aimed to explore the effects of STA on the autophagy in DR progression in vivo and in vitro.

Methods

High glucose-treated human retinal microvascular endothelial cells (HRMECs) and STA-treated rats were used to establish DR model. The reactive oxygen species (ROS) and inflammatory factor levels (TNF-α, IL-1β, and IL-6) were determined using corresponding kits. Additionally, the cell growth was analyzed using CCK-8 and EdU assays. Besides, LC3BII, p62, p-AMPKα, AMPKα, and SIRT1 protein levels were measured using Western blot. The LC3BII and SIRT1 expressions were also determined using immunofluorescence.

Results

The results showed that STZ decreased the ROS and inflammatory factor levels in the HG-treated HRMECs. Besides, after STA treatment, the beclin-1, LC3BII, p-AMPKα, and SIRT1 levels were increased, and p62 was decreased in the HG-treated HRMECs and the retinal tissue of STZ-treated rats.

Conclusion

In conclusion, this study demonstrated that STA effectively relieved the inflammation and promoted the autophagy in DR progression in vivo and in vitro through activating the AMPK/SIRT1 signaling pathway.

Novel 2,6-disubstituted benzofuran-3-one analogues improve cerebral ischemia/reperfusion injury via neuroprotective and antioxidative effects

There are no highly effective and safe medicines for clinical treatment of ischemic stroke, although the natural product 3-n-butylphthalide (NBP) has been approved in China for mild and moderate ischemic stroke. To discover more potent anti-cerebral ischemic agents and overcome the low stability by phthalide derivatives, benzofuran-3-one was selected as a core moiety and two types of nitric oxide (NO)-donating groups were incorporated into the structure. In this work, a series of 2,6-disubstituted benzofuran-3-one derivatives were designed and synthesised as NBP analogues, and tested as neuroprotective and antioxidative agents. Compounds 5 (without an NO donor) and 16 (with an NO donor) displayed more potent neuroprotective effects than the established clinical drugs Edaravone and NBP. More importantly, 5 and 16 also exhibited good antioxidative activity without cytotoxicity in rat primary neuronal and PC12 cells. Most active compounds showed good blood-brain barrier permeability in a parallel artificial membrane permeability assay. Furthermore, compound 5 reduced the ischemic infarct area significantly in rats subjected to ischemia/reperfusion injury, downregulated ionised calcium-binding adaptor molecule 1 and glial fibrillary acidic protein in inflammatory cells, and upregulated nerve growth factor.

Lactic Dehydrogenase to Albumin Ratio Is Associated With the Risk of Stroke-Associated Pneumonia in Patients With Acute Ischemic Stroke

Background: Stroke-associated pneumonia (SAP) is one of the common complications of stroke patients. Higher lactic dehydrogenase (LDH) and lower albumin levels were associated with SAP, but the contribution of the LDH to albumin ratio (LAR) to the risk of SAP in acute ischemic stroke (AIS) patients remained unclear. Methods: A total of 3173 AIS patients were included in this study, divided into SAP (n = 417) and non-SAP groups (n = 2756). Characteristics were compared between these two groups. The receiver operating characteristic curves (ROC) were used to evaluate the discrimination ability of the LAR, LDH, and albumin levels in predicting SAP. Logistic regression analysis was furtherly adopted to estimate the association between LAR and SAP. We also used the restricted cubic spline (RCS) to clarify the relationship between LAR and the risk of SAP. Results: LAR in the SAP group was significantly higher than that of the non-SAP group (8.75 ± 4.58 vs. 6.10 ± 2.55, P < 0.001). According to the results of ROC, LAR had the highest prognostic accuracy compared to LDH and albumin (P < 0.05). Besides, the logistic regression model showed that higher LAR (LAR > 6.75) were more vulnerable to SAP (OR, 2.80; 95% CI, 2.18-3.59, P < 0.001), controlling the confounders. The RCS model showed that there was a non-linear relationship between LAR and the risk of SAP. Conclusion: High LAR was associated with an increased risk of SAP in patients with AIS. LAR may be a potential predictor for the incidence of SAP. Appropriate prevention measures were needed in patients with high LAR (LAR > 6.75).