The surviving brain tissue undergoes secondary degeneration long after an ischemic stroke. Cathepsin B plays dual roles as both a scavenger and an executor. Using a mouse model of ischemic stroke, we specifically investigated the mechanism by which inhibiting Cathepsin B with CA074 methyl ester (CA-074Me) during the chronic phase of stroke exerts a protective effect. In the intervention group, CA-074Me (20 μg CA-074Me/1 μl DMSO) was stereotaxically injected in the right ventricle, and, 30 min later, the animals were subjected to develop transient middle cerebral artery occlusion and reperfusion (tMCAO/R) stroke model with modified Longa method. In the model group, 1 μl DMSO was given in the right ventricle instead and the sham-operated group received 1 μl DMSO in the right ventricle without arterial occlusion. We evaluated the effects of inhibition of Cathepsin B on the nervous system after tMCAO/R injury by combined use behavioral tests, neurological deficit scoring, Western blot and other pharmacological methods and explored the underlying mechanism. After tMCAO/R, sustained upregulation and activation of Cathepsin B was noticed in the ipsilateral hippocampus CA1 zone and CA-074Me ameliorated the parallel lysosome-mitochondria damage, decreased apoptosis, improved the cognitive dysfunction, but had no effects on levels of mouse anxiety or depression. Furthermore, CA-074Me reduced neuroinflammation, levels of oxidative stress and mitochondria fission. Inhibition of Cathepsin B alleviates mitochondrial abnormalities in the ipsilateral hippocampus CA1 zone 28 days after tMCAO/R by suppressing Drp-1mediated excessive mitochondrial fission. This, in turn, reduces neuronal apoptosis, ameliorates neuroinflammation, and mitigates oxidative stress and neuronal damage, indicating Cathepsin B may serve as a potential therapeutic target for remote secondary degeneration following acute ischemic stroke.
The 2022 US Cancer Statistics show that breast cancer is one of the most common cancers in women. Epidemiology has shown that adding flavonoids to the diet inhibits cancers that arise in particular women, such as cervical cancer, ovarian cancer, and breast cancer. Although there have been research reports on apigenin (API) and breast cancer, its anti-tumor effect and potential mechanism on breast cancer have not yet been clarified. Therefore, in this study, we used 4T1 cells and a 4T1 xenograft tumor mouse model to investigate the antitumor effect of API on breast cancer and its underlying mechanism. In vitro, we used MTT, transwell, staining, and western blotting to investigate the inhibitory effect of apigenin on 4T1 and the underlying molecular mechanism. In vivo by establishing a xenograft tumor model, using immunohistochemistry, and flow cytometry to study the inhibitory effect of apigenin on solid breast tumors and its effect on the tumor immune microenvironment. The results showed that API can induce breast cancer cell apoptosis through the PI3K/AKT/Nrf2 pathway and can improve the tumor immune microenvironment in mice with breast tumors, thereby inhibiting the growth of breast cancer. Thus, API may be a promising agent for breast cancer treatment.
Background Doxorubicin (DOX) causes lethal cardiotoxicity, which limits its clinical utility. The molecular mechanisms and effective strategies to combat its cardiotoxicity need further exploration. DT-010, a novel conjugate of danshensu (DSS) and tetramethylpyrazine(TMP), is considered a promising candidate for treating DOX-induced cardiotoxicity. In this study, we aimed to investigate the underlying molecular mechanisms of DOX-induced cardiotoxicity and the cardioprotective effects of DT-010.Methods Isobaric tags for relative and absolute quantitation (iTRAQ) in proteomics analysis was employed to analyze the differentially expressed proteins in DOX-injuried hearts. Gene ontology (GO) enrichment analysis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were carried out to evaluated the potential mechanisms of DOX-induced cardiotoxicity. The effects of NCAM1 on DOX-induced cardiotoxicity in H9c2 cells, as well as the cardioprotection of DT-010 were assessed through NACM1siRNA transfection, cell viability assay, cell apoptosis staining, reactive oxygen species measurement, and western blotting.Results Proteomics analysis revealed that several signaling pathways, including the tricarboxylic acid (TCA) cycle and oxidative phosphorylation, were involved in DOX-induced cardiotoxicity. NCAM1 is one of the significantly changed proteins. DT-010 treatment regulated NCAM1 protein expression. Silencing NCAM1 in DOX-treated H9c2 cells decreased cell viability, increased cell apoptosis and reactive oxygen species (ROS) generation, and attenuated the cardioprotective effects of DT-010. Furthermore, NCAM1 knockdown promoted p38 activation and inhibited the expressions of peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1 alpha) and heme oxygenase-1 (HO-1) in DOX-treated cells.Conclusion These findings indicate a definite role of NCAM1 in DOX-induced cardiotoxicity and DT-010-exerted cardioprotection, which is mediated through the p38 and Sirt1/PGC-1 alpha/HO-1 pathway.
Sarcopenia is becoming prevalent in older or inactive patients, which is placing a heavy burden on the social health system. Studies on the pathogenesis of sarcopenia mainly focus on adipose tissue, myoglobin autophagy, and mitochondrial dysfunction. Up to now, non-drug treat-ment has been the main way to treat sarcopenia, and there are no drugs specially approved for the treatment of sarcopenia. Here, the pathophysiology and treatment methods of sarcopenia have been summarized, and new drugs for sarcopenia to be researched and developed in the future have been prospected.
A series of novel isobenzofuran-1(3H)-one derivatives were designed and synthesized as antidepressants. Firstly, the serotonin reuptake inhibition of these compounds was tested in vitro, and most of them exhibited activity. Particularly, compounds 9d, 10a, and 10c demonstrated superior inhibitory effects and possibly avoided addiction via the μ-opioid receptor and CCK-B receptor. Secondly, the antidepressant effect of compound 10a was evaluated using chronic restraint stress (CRS)-induced mice. The results showed that compound 10a significantly improved CRS-induced depression-like behavior by increasing the neurotransmitters 5-HT in the cortex and THP2 expression in the hippocampus. Thirdly, compound 10a was further investigated and found to enhance CRS-induced hippocampal neuron damage recovery and elevate the expression of synaptic-associated proteins such as BDNF, TrkB, PSD95, and Spinophilin in CRS-induced mice. These findings suggested that novel isobenzofuran-1(3H)-one derivative showed efficacy in treating depression, with compound 10a emerging as a potential lead compound warranting further investigation.
Red algal polysaccharide is a good potential medical resource. Different red algal polysaccharides have different structural characteristics and rich biological activities. Previous studies have identified some structural information of sulfated polysaccharide (GNP, 25.8 kDa) from red algae, Gelidium crinale and found that GNP has excellent anti-inflammatory, antioxidant and anti-tumor activities. On this basis, this study investigated the effect of GNP on atherosclerosis, which is closely related to antioxidant and anti-inflammatory mechanisms and usually coexists and interacts with hypertension. This study investigated the inhibitory activity of GNP on angiotensin-converting enzyme (ACE) and its mechanism on oxidized low-density lipoprotein (ox-LDL)-induced HUVEC atherosclerosis. The results showed that GNP inhibits the up-regulation of cell adhesion molecules and oxidized low-density lipoprotein receptor-1 (LOX-1). GNP can regulate mitogen-activated protein kinases (MAPK), nuclear factor kappa B (NF-κB) and PI3K/AKT signal pathways, inhibit apoptosis, invasion and migration. Meanwhile, GNP (IC50 = 269.2 μg/mL) antagonizes ACE by competitive binding mode, and it can reduce systolic blood pressure (SBP) of spontaneously hypertensive rats (SHR). It provides a theoretical basis for GNP as a potential substance for the prevention and treatment of atherosclerosis.
In the early stage, oxidized low density lipoprotein (ox-LDL) caused atherosclerosis, followed by human umbilical vein endothelial cells (HUVEC) damage, leading to a variety of cardiovascular related diseases. This study investigated the mechanism of nonapeptide (EMFGTSSET, ETT) isolated from in vitro gastrointestinal digestion of Isochrysis zhanjiang on endothelial cell inflammation and apoptosis induced by ox-LDL in atherosclerosis. At the cellular level, the results shown that ETT inhibited the up-regulation of oxidized low-density lipoprotein receptor-1 (LOX-1) induced by ox-LDL. Furthermore, ETT inhibited the fluorescence intensity of ROS, inflammatory factors (interleukin-6, interleukin-1β, and tumor necrosis factor-α) and the expression of cell adhesion molecules (vascular cell adhesion protein 1 and intercellular cell adhesion molecule-1). In addition, it also upregulates nuclear red blood cell 2 related factor 2 (Nrf2), heme oxygenase-1 (HO -1), p-Akt, and bcl-2 levels. But down-regulated the expression of p-p65, p-IκB-α, p-p38, p-ERK, p-JNK, bax, and cleaved caspase-9/-3 (c-c-9/-3), thereby inhibited ox-LDL induction inflammation and apoptosis of atherosclerosis. Through molecular docking, it was judged that the stable interaction between ETT and LOX-1 and VCAM-1 was maintained through hydrogen bonding. These results can provide a theoretical basis for ETT as a potential substance for the prevention and treatment of atherosclerosis, and further improve the value of Isochrysis zhanjiangensis.
Microalgae are primary producers in marine ecosystems, and have been diffusely used in medicine and food. In this research, we evaluated the protective effects of polypeptides from microalgae, Isochrysis zhanjiangensis (EMFGTSSET, ETT) on endothelial injury in angiotensin II (Ang II)-induced human umbilical vein endothelial cells (HUVEC). The results showed that ETT inhibited the fluorescence intensity of intracellular reactive oxygen species (ROS), and reduces the expression of related cytokines, such as IL-1β, IL-8, TNF-α, iNOS, COX-2, ET-1, AT-1, and adhesion factor. It blocks inflammation and apoptosis through mitogen-activated protein kinases (MAPK), nuclear factor κB (NF-κB) and serine/threonine kinase (Akt) signal pathways, thereby alleviating endothelial damage. Meanwhile, ETT (IC50 = 15.08 μM) antagonizes Angiotensin-I Converting Enzyme (ACE) in a non-competitive binding mode, and has an antihypertensive effect in spontaneously hypertensive rats (SHR). Therefore, ETT has excellent effect in regulating hypertension, can become the main component of potential functional food for the prevention of cardiovascular diseases, and further improve the use value of Isochrysis Zhanjiangensis.
Nitroglycerin (NTG) is recommended as the first-line drug in angina pectoris though its prolonged use impacts nitroglycerin tolerance. In this study, we investigated the preventive effect of Tetramethylpyrazine (TMP), a famous Chinese medicine used for cardiovascular diseases, on NTG-induced tolerance and further explained the underlying mechanism of its action. The results revealed that pretreatment of TMP improved NTG-induced tolerance in vitro thoracic aorta rings and in rats. Proteomic analysis showed oxidative stress and ribosome proteins dyshomeostasis in NTG-tolerance vessels. TMP attenuated the oxidative stress by enhancing the protein expression of ALDH2, Nrf2 and HO-1. In addition, TMP recovered the down-regulated expression of RpL10a induced by nitroglycerin. Therefore, TMP could prevent nitroglycerin tolerance in rats, which may be mediated by up-regulation of ALDH2 and Nrf2/HO-1 signaling pathway and involved in the restoration of ribosome homeostasis. These findings indicate the potential of TMP as a promising medicine for preventing the development of nitroglycerin-induced tolerance.
Introduction: Doxorubicin (DOX), an anthracycline antitumor agent, has been widely used against various solid tumors and hematological malignancies. However, the clinical application of DOX is restricted by its multiple organ toxicity including nephrotoxicity. This study investigated the protective effects and mechanisms of dexrazoxane (DZR) against DOX-induced nephropathy in rats. Methods: Male Sprague Dawley rats received 2.5 mg/kg DOX once a week for 5 consecutive weeks. 24-h urinary protein and renal function injury biomarkers were determined to evaluate the renal function. Histopathological changes and glomerulosclerosis were examined by hematoxylin and eosin and periodic acid-Schiff staining. The change of renal ultrastructure in the DOX-induced rats was observed by the electron microscopy. The renal apoptosis was detected by TUNEL staining and measured the protein expression of Caspase-3, Bcl-2, and Bax. Renal interstitial fibrosis was determined by Masson staining and immunohistochemistry examination. The levels of vimentin, alpha-smooth muscle actin (α-SMA), and transforming growth factor β (TGF-β) in kidney tissue were detected by Western blot. Results: DZR pretreatment markedly raised the survival rate and improved the renal dysfunction in DOX-treated rats. DZR ameliorated DOX-induced histopathological lesion of glomerular and tubular and apoptosis. DZR restored the oxidant/antioxidant balance via regulating the levels of MDA, SOD, and TAC. DZR reduced DOX-induced collagen IV deposition and renal interstitial fibrosis and downregulated the fibrosis-related protein expressions of vimentin, α-SMA, and TGF-β1. Conclusion: Our results suggest DZR exerted its protective effects against DOX-induced nephropathy through inhibition of lipid peroxidation, apoptosis, and fibrosis.
N-甲基-D-天冬氨酸(NMDA)受体是一种离子型谷氨酸受体,在中枢神经系统兴奋性的突触传递、可塑性和兴奋毒性中起着关键作用,与机体的记忆、学习和情绪密切相关.本文从结构分布和生理活性这两方面详细总结了N-甲基-D-天冬氨酸受体各亚型的特点,介绍并汇总了目前研究较多的N-甲基-D-天冬氨酸受体拮抗剂,为N-甲基-D-天冬氨酸受体在神经性疾病中的相关研究提供信息依据.
BACKGROUND:Acute lung injury (ALI) is a serious respiratory disease with a high mortality rate, and there is an urgent need for a more effective treatment strategy. Andrographolide derivative AL-1 has been identified to possess anti-inflammatory activity. However, whether it could reduce LPS-induced lung injury in mice through inhibiting NLRP3 inflammasome activation and protecting lung permeability has not yet been elucidated. In the present research, we investigated the protective effect of AL-1 on ALI mice and demonstrated the potential mechanisms.METHODS:Male Balb/c mice were anesthetized with isoflurane, and ALI mice were induced by intratracheal instillation of LPS. The mice were euthanized after LPS administration for 12 h, then bronchoalveolar lavage fluid (BALF) and lung tissues were collected. The levels of inflammatory factors were measured by ELISA assay, and HE staining and lung injury scoring were used to evaluate the pathological changes in the pulmonary tissues. Immunohistochemistry and immunofluorescence examination were conducted to detect the expression levels of related proteins. Western blot was performed to measure the levels of NLRP3 inflammasome and tight junction proteins.RESULTS:The study indicated that AL-1 effectively alleviated lung injury by reduction of proinflammatory cytokine levels, MPO activity, lung W/D ratio, and total protein levels. Furthermore, AL-1 improved pathological changes in lung tissue and significantly reduced the infiltration of inflammatory cells. Administration with AL-1 markedly inhibited the expression of NLRP3, ASC, Caspase-1, IL-1β, gasdermin D (GSDMD), and VCAM-1 but increased the expression of ZO-1, Occludin, JAM-A, and Claudin-1.CONCLUSION:Taken together, these results demonstrated that AL-1 ameliorated pulmonary damage by inhibiting the activation of the NLRP3 inflammasome pathway and restoring TJ protein expression.
A catalytic asymmetric halocycloetherification process is developed to achieve enantioenriched quaternary 2,2-disubstituted morpholines using an organo-catalyst.
Sceletium tortuosum (SCT) has been utilized medicinally by indigenous Koi-San people purportedly for mood elevation. SCT extracts are reported to be neuroprotective and have efficacy in improving cognition. However, it is still unclear which of the pharmacological mechanisms of SCT contribute to the therapeutic potential for neurodegenerative disorders. Hence, this study investigated two aspects–firstly, the abilities of neuroprotective sub-fractions from SCT on scavenging radicals, inhibiting some usual targets relevant to Alzheimer’s disease (AD) or Parkinson’s disease (PD), and secondly utilizing the network pharmacology related methods to search probable mechanisms using Surflex-Dock program to show the key targets and corresponding SCT constituents. The results indicated sub-fractions from SCT could scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, inhibit acetylcholinesterase (AChE), monoamine oxidase type B (MAO-B) and N-methyl-D-aspartic acid receptor (NMDAR). Furthermore, the results of gene ontology and docking analyses indicated the key targets involved in the probable treatment of AD or PD might be AChE, MAO-B, NMDAR subunit2B (GluN2B-NMDAR), adenosine A2A receptor and cannabinoid receptor 2, and the corresponding constituents in Sceletium tortuosum might be N-trans-feruloyl-3-methyldopamine, dihydrojoubertiamine and other mesembrine type alkaloids. In summary, this study has provided new evidence for the therapeutic potential of SCT in the treatment of AD or PD, as well as the key targets and notable constituents in SCT. Therefore, we propose SCT could be a natural chemical resource for lead compounds in the treatment of neurodegenerative disorders.
Sceletium tortuosum (SCT) has been utilized medicinally by indigenous Koi-San people purportedly for mood elevation. SCT extracts are reported to be neuroprotective and have efficacy in improving cognition. However, it is still unclear which of the pharmacological mechanisms of SCT contribute to the therapeutic potential for neurodegenerative disorders. Hence, this study investigated two aspects-firstly, the abilities of neuroprotective sub-fractions from SCT on scavenging radicals, inhibiting some usual targets relevant to Alzheimer's disease (AD) or Parkinson's disease (PD), and secondly utilizing the network pharmacology related methods to search probable mechanisms using Surflex-Dock program to show the key targets and corresponding SCT constituents. The results indicated sub-fractions from SCT could scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, inhibit acetylcholinesterase (AChE), monoamine oxidase type B (MAO-B) and N-methyl-D-aspartic acid receptor (NMDAR). Furthermore, the results of gene ontology and docking analyses indicated the key targets involved in the probable treatment of AD or PD might be AChE, MAO-B, NMDAR subunit2B (GluN2B-NMDAR), adenosine A2A receptor and cannabinoid receptor 2, and the corresponding constituents in Sceletium tortuosum might be N-trans-feruloyl-3-methyldopamine, dihydrojoubertiamine and other mesembrine type alkaloids. In summary, this study has provided new evidence for the therapeutic potential of SCT in the treatment of AD or PD, as well as the key targets and notable constituents in SCT. Therefore, we propose SCT could be a natural chemical resource for lead compounds in the treatment of neurodegenerative disorders.
1. Retrorsine (RTS) is a pyrrolizidine alkaloid (distributed in many medicinal plants) that has significant hepatotoxicity. Here, we aimed to determine the daily variations in RTS hepatotoxicity (chronotoxicity) in mice, and to investigate the role of metabolism in generating RTS chronotoxicity.2. Acute toxicity and pharmacokinetic studies were performed with mice after RTS administration at different times of the day. Hepatotoxicity was assessed by measuring plasma ALT (alanine aminotransferase) and AST (aspartate aminotransferase) levels. mRNA and proteins were determined by qPCR and Western blotting, respectively. Time-dependent in vitro metabolism of RTS was assessed by using mouse liver microsomes.3. We found that RTS toxicity was more severe in the dark phase (zeitgeber time 14 or ZT14 and ZT18) than in the light phase (ZT2 and ZT6). This chronotoxicity was associated with a dosing time difference in the systemic exposures of RTS and a pyrrolic ester metabolite (a cause of hepatotoxicity, measured by the levels of pyrrole-GSH conjugate and pyrrole-protein adducts due to a high chemical reactivity). Moreover, the CYP3A11 (a major enzyme for RTS bioactivation) inhibitor ketoconazole decreased the production of pyrrole-GSH conjugate and abrogated diurnal rhythm in RTS metabolism. In addition, E4bp4 (a circadian regulator of Cyp3a11) ablation abolished the rhythm of CYP3A11 expression and abrogated the dosing time-dependency of RTS toxicity.4. In conclusion, RTS chronotoxicity in mice was attributed to time-varying hepatic metabolism regulated by the circadian clock. Our findings have implications for reducing pyrrolizidine alkaloid-induced toxicity via a chronotherapeutic approach.
Authors contribution: Authors contributed equally to this paper or author contribution: Yangwen Luo performed the experiments, data collection, analysis, reference search and preparation of manuscript; Isadore Kanfer and Srinivas Patnala; contributed to identification and supply of Sceletium plant material and provided guidance on alkaloidal components and their separation and further editing and proof reading the manuscript; Luchen Shan and Lipeng Xu; provided guidance on pharmacological experiments; Yi Dai; contributed towards guidance of UPLCqTOF-MSE experiments; Pei Yu; contributed towards research literature, project administration, and proof reading.
Gelidium crinale, the red algae belonging to Geliaceae Gelidium, is a traditional edible and industrial alga in China. A sulfated polysaccharide (GNP) is successfully separated from Gelidium crinale by acid extraction and two-step column chromatography. Chemical analysis showed that the molecular weight of GNP was 25.8 kDa and the monosaccharide composition had the highest galactose content and confirmed the presence and content (16.5%) of sulfate by Fourier transform infrared spectroscopy (FT-IR) spectrometry as well as barium chloride-gelatin methods. In addition, the effect of GNP on lipopolysaccharide (LPS)-induced oxidative stress and inflammation in macrophages was also evaluated. The research results showed that GNP had fairly strong scavenging activities on 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical, hydroxyl radical, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and had Fe2+-chelating ability in a dose-dependent manner. At the same time, it significantly inhibits the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and the production of pro-inflammatory cytokines in RAW 264.7 cells induced by LPS through blocking the mitogen-activated protein kinase (MAPK)/nuclear factor kappa beta (NF-κB) signaling pathway. These results indicate that GNP may be a latent component anti-inflammation in pharmaceutical and functional food industries.
The molecular events underlying aristolochic acid (AA) nephropathy are poorly understood, and specific therapies for treatment of AA nephropathy are still lacking. Here we aimed to investigate a potential role of REV-ERBα and ferroptosis in renal injury induced by aristolochic acid I (AAI), a typical AA. The regulatory effects of REV-ERBα on AAI-induced renal injury were determined using kidney-specific Rev-erbα knockout mice. Ferroptosis was assessed based on measurements of iron, GSH, and GPX4. Targeted antagonism of REV-ERBα to alleviate AAI-induced renal injury and ferroptosis was assessed using the small molecule antagonist SR8278. mRNAs and proteins were quantified by qPCR and Western blotting, respectively. We first showed that REV-ERBα was upregulated and its target BMAL1 was downregulated in the kidney of mice with AAI nephropathy. Upregulation of REV-ERBα protein was confirmed in aristolactam I (ALI, a nephrotoxic metabolite of AAI)-treated mRTECs. We also observed enhanced ferroptosis (known to be regulated by REV-ERBα) in mice with AAI nephropathy and in ALI-treated mRTECs. Kidney-specific knockout of Rev-erbα reduced the sensitivity of mice to AAI-induced ferroptosis and renal injury. Furthermore, knockdown of Rev-erbα by siRNA or SR8278 (a REV-ERBα antagonist) treatment attenuated ALI-induced ferroptosis in mRTECs. Moreover, REV-ERBα antagonism by SR8278 alleviated ferroptosis and renal injury caused by AAI in mice. In conclusion, we identify REV-ERBα as a regulator of AAI-induced renal injury via promoting ferroptosis. Targeting REV-ERBα may represent a promising approach for management of AAI nephropathy.
We report a catalytic asymmetric halocyclization protocol to furnish benzoxazepinones and benzoxazecinones using (DHQ)2PHAL as the catalyst. Various halogenated benzoxazepinones and benzoxazecinones were achieved in excellent yields and enantioselectivities under mild conditions. A cocrystal structure of the substrate and the catalyst was studied.