In situ injectable hydrogel encapsulating Mn/NO-based immune nano-activator for prevention of postoperative tumor recurrence

Postoperative tumor recurrence remains a predominant cause of treatment failure. In this study, we developed an in situ injectable hydrogel, termed MPB-NO@DOX + ATRA gel, which was locally formed within the tumor resection cavity. The MPB-NO@DOX + ATRA gel was fabricated by mixing a thrombin solution, a fibrinogen solution containing all-trans retinoic acid (ATRA), and a Mn/NO-based immune nano-activator termed MPB-NO@DOX. ATRA promoted the differentiation of cancer stem cells, inhibited cancer cell migration, and affected the polarization of tumor-associated macrophages. The outer MnO2 shell disintegrated due to its reaction with glutathione and hydrogen peroxide in the cytoplasm to release Mn2+ and produce O2, resulting in the release of doxorubicin (DOX). The released DOX entered the nucleus and destroyed DNA, and the fragmented DNA cooperated with Mn2+ to activate the cGAS-STING pathway and stimulate an anti-tumor immune response. In addition, when MPB-NO@DOX was exposed to 808 nm laser irradiation, the Fe-NO bond was broken to release NO, which downregulated the expression of PD-L1 on the surface of tumor cells and reversed the immunosuppressive tumor microenvironment. In conclusion, the MPB-NO@DOX + ATRA gel exhibited excellent anti-tumor efficacy. The results of this study demonstrated the great potential of in situ injectable hydrogels in preventing postoperative tumor recurrence.

Persimmon leaf flavonoid promotes brain ischemic tolerance

Persimmon leaf flavonoid has been shown to enhance brain ischemic tolerance in mice, but its mechanism of action remains unclear. The bilateral common carotid arteries were occluded using a micro clip to block blood flow for 10 minutes. After 10 minutes of ischemic preconditioning, 200,100, and 50 mg/kg persimmon leaf flavonoid or 20 mg/kg ginaton was intragastrically administered per day for 5 days. At 1 hour after the final administration, ischemia/reperfusion models were estab- lished by blocking the middle cerebral artery for 2 hours. At 24 hours after model establishment, compared with cerebral ischemic rats without ischemic preconditioning or drug intervention, plasma endothelin, thrombomodulin and yon Willebrand factor levels significantly decreased and intercel- lular adhesion molecule-1 expression markedly reduced in brain tissue from rats with ischemic pre- conditioning. Simultaneously, brain tissue injury reduced. Ischemic preconditioning combined with drug exposure noticeably improved the effects of the above-mentioned indices, and the effects of 200 mg/kg persimmon leaf flavonoid were similar to 20 mg/kg ginaton treatment. These results indicate that ischemic preconditioning produces tolerance to recurrent severe cerebral ischemia. However, persimmon leaf flavonoid can elevate ischemic tolerance by reducing inflammatory reactions and vascular endothelial injury. High-dose persimmon leaf flavonoid showed an identical effect to ginaton.

Persimmon leaf flavonoid induces brain ischemic tolerance in mice

The persimmon leaf has been shown to improve cerebral ischemic outcomes; however, its mechanism of action remains unclear. In this study, mice were subjected to 10 minutes of ischemic preconditioning, and persimmon leaf flavonoid was orally administered for 5 days. Results showed that the persimmon leaf fiavonoid significantly improved the content of tissue type plasminogen activator and 6-keto prostaglandin-F1 a in the cerebral cortex, decreased the content of thromboxane B2, and reduced the content of plasminogen activator inhibitor-1 in mice. Following optical microscopy, persimmon leaf flavonoid was also shown to reduce cell swelling and nuclear hyperchromatism in the cerebral cortex and hippocampus of mice. These results suggested that persimmon leaf fiavonoid can effectively inhibit brain thrombosis, improve blood supply to the brain and relieve ischemia-induced pathological damage, resulting in brain ischemic tolerance.

Effect of Schisandra chinensis polysaccharide on intracerebral acetylcholinesterase and monoamine neurotransmitters in a D-galactose-induced aging brain mouse model

BACKGROUND： The most prominent characteristic of brain aging is decreased learning and memory ability. The functions of learning and memory are closely related to intracerebral acetylcholinesterase （ACHE） and monoamine neurotransmitter activity. Previous studies have shown that Schisandra chinensis polysaccharide has an anti-aging effect. OBJECTIVE： To explore the effects of Schisandra chinensis polysaccharide on AChE activity and monoamine neurotransmitter content, as well as learning and memory ability in a D-galactose-induced aging mouse brain model compared with the positive control drug Kangnaoling. DESIGN, TIME AND SETTING： Completely randomized, controlled experiment based on neurobiochemistry was performed at the Pharmacological Laboratory, Henan University of Traditional Chinese Medicine from September to December 2003. MATERIALS： Schisandra chinensis was purchased from Henan Provincial Medicinal Company. Schisandra chinensis polysaccharide was obtained by water extraction and alcohol precipitation. Kangnaoling pellets were provided by Liaoning Tianlong Pharmaceutical （batch No. 20030804; state drug permit No. H21023095）. A total of 50 six-week-old Kunming mice were randomly divided into five groups： blank control, model, Kangnaoling, high and low dosage Schisandra chinensis polysaccharide groups, with 10 mice per group. METHODS： Mice in the blank control group were subcutaneously injected with 0.5 mL/20 g normal saline into the nape of the neck each day, while the remaining mice were subcutaneously injected with 5% D-galactose saline solution （0.5 mL/20 g） in the nape for 40 days to induce a brain aging model. On day 11, mice in the high and low dosage Schisandra chinensis polysaccharide groups were intragastrically infused with 20 mg/mL and 10 mg/mL Schisandra chinensis polysaccharide solution （0.2 mL/10 g）, respectively. Mice from the Kangnaoling group were intragastrically infused with 35 mg/mL Kangnaoling suspension （0.2 mL/10 g）, and the mice in the model group were intragastrically infused with the same volume of normal saline （0.2 mL/10 g） once per day for 30 consecutive days. MAIN OUTCOME MEASURES： Two hours after the final administration, pathohistological changes in the cerebral cortex and hippocampus were observed using hematoxylin ＆ eosin staining. AChE activity was detected using chromatometry. Monoamine neurotransmitter content was measured using fluorimetry. Learning and memory was measured using the step down test and darkness avoidance test. RESULTS： Both Schisandra chinensis polysaccharide and Kangnaoling improved pathological injury to the cerebral cortex and hippocampus in a mouse model of brain aging. Compared with the blank control group, AChE activity and content of norepinephrine （NA）, dopamine （DA）, and 5-hydroxytryptamine （5-HT） were significantly decreased in the model group （P 〈 0.01 ）. In contrast, AChE activity and NA, DA, and 5-HT levels significantly increased in the Kangnaoling and high dosage Schisandra chinensis polysaccharide groups （P 〈 0.01）, while NA levels significantly increased in the low dosage Schisandra chinensis polysaccharide group （P 〈 0.01）. Drug treatment improved learning and memory abilities （P 〈 0.01 or P 〈 0.05）. CONCLUSION： Schisandra chinensis polysaccharide significantly increased levels of central neurotransmitters and improved learning and memory in a mouse model of brain aging. The effects of Schisandra chinensis polysaccharide were equal to that of Kangnaoling pellets.

Characterization of SHARPIN knockout Syrian hamsters developed using CRISPR/Cas9 system

Background : SHARPIN (SHANK- associated RH domain interactor) is a component ofthe linear ubiquitination complex that regulates the NF- κB signaling pathway. To betterunderstand the function of SHARPIN, we sought to establish a novel geneticallyengineered Syrian hamster with SHARPIN disruption using the CRISPR/Cas9 system.Methods : A single- guide ribonucleic acid targeting exon 1 of SHARPIN gene was designedand constructed. The zygotes generated by cytoplasmic injection of the Cas9/gRNA ribonucleoprotein were transferred into pseudopregnant hamsters. Neonatalmutants were identified by genotyping. SHARPIN protein expression was detectedusing Western blotting assay. Splenic, mesenteric lymph nodes (MLNs), and thymicweights were measured, and organ coefficients were calculated. Histopathologicalexamination of the spleen, liver, lung, small intestine, and esophagus was performedindependently by a pathologist. The expression of lymphocytic markers and cytokineswas evaluated using reverse transcriptase- quantitative polymerase chain reaction.Results : All the offspring harbored germline- transmitted SHARPIN mutations.Compared with wild- type hamsters, SHARPIN protein was undetectable in SHARPIN −/−hamsters. Spleen enlargement and splenic coefficient elevation were spotted inSHARPIN −/− hamsters, with the descent of MLNs and thymuses. Further, eosinophilinfiltration and structural alteration in spleens, livers, lungs, small intestines, and esophagiwere obvious after the deletion of SHARPIN. Notably, the expression of CD94 and CD22 was downregulated in the spleens of knockout (KO) animals. Nonetheless,the expression of CCR3, CCL11, Il4 , and Il13 was upregulated in the esophagi. Theexpression of NF- κB and phosphorylation of NF- κB and IκB protein significantly diminishedin SHARPIN −/− animals.Conclusions : A novel SHARPIN KO hamster was successfully established using theCRISPR/Cas9 system. Abnormal development of secondary lymphoid organs andeosinophil infiltration in multiple organs reveal its potential in delineating SHARPINfunction and chronic inflammation.

COVID-19 Resulting in Potential Hearing Damage of Rodents

Objectives To find out the association between the sensorineural hearing loss and coronavirus disease 2019(COVID-19),the expression of ACE2 and TMPRSS2 in hamsters and mice was detected.Design Using the public data from the National Center for Biotechnology Information and the Global Initiative on Sharing All Influenza Data,the expression of ACE2 and TMPRSS2 at the transcriptomic,DNA,and protein levels of ACE2 in the brain,inner ear,and muscle from the golden Syrian hamsters(Mesocricetus auratus)and mice(Mus musculus)was assessed.Results We identified ACE2 and TMPRSS2 expressed at different levels in the inner ear and brain at DNA and transcriptomic levels of both mice and hamsters.The protein expression from the brain and inner ear showed a similar pattern,while the expression of ACE2 from the inner ear was relatively higher than that from the muscle.Conclusion Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)shows genetic potential to infect the hearing system of rodents and lead to sudden sensorineural hearing loss that can be used as a characteristic to detect asymptomatic patients of COVID-19.

Ginkgo paste improves tinea corporis in a guinea pig model

To investigate the effects of Ginkgo paste for external use on tinea corporis in a guinea pig model.The guinea pig tinea corporis model were induced by infection with Trichophyton mentagrophytes strains.And then,high and low doses of Ginkgo water-paste and alcohol-paste were administrated to the animals.The symptom,tinea corporis skin lesions and histopathological aspects of guinea pig were analyzed.High and low doses of Ginkgo alcohol-paste and Ginkgo water-paste could significantly reduced the tinea corporis symptom(P<0.01),increased negative rate of strain culture(P<0.01),and improved pathological changes of tinea corporis(P<0.01).The best efficacy was observed in high dose ginkgo alcohol paste group.These results suggest that Ginkgo paste exhibits the efficacy to treat tinea corporis in a guinea pig model.

Analysis of the Influence of Different Drying Methods on the Active Ingredients of Fresh Medicine

The heating area of the material is large and the thermal efficiency is high,but it is n ecessary to control the suitable drying temperature ofdiffere nt medici nal materials to preserve the effective in gredients.D iff ere nt kinds of Chinese medicine need different drying conditions to fulfill good drying requirements.Natural drying in the shade is one of the traditional drying methods,which takes a long time and is easily affected by the weather.The water volatilizes slowly.It is prone to mildew and discoloration during the drying process.However,it can better preserve the volatile oil components of Chinese medicine.The hot-air drying machine has lower requirements.The medicinal materials have a large heating area and high thermal efficiency,but it is necessary to control the appropriate drying temperature of different medicinal materials in order to preserve the active ingredients of the medicinal materials;it is not suitable for medicinal materials that stick and bind easily.The microwave drying method possesses superiority in drying some valuable medicinal materials such as Ren she n(Radix et Rhizoma Ginseng)and Lurong(Co「nu Cervi Pantotrichum),and the effective ingredients are preserved at a high degree;it can also achieve the purpose of killing enzymes and protecting glycosides and have a good bactericidal effect,but it is not suitable for Chinese medicines containing heat-sensitive ingredients,because it will destroy most of the proteins,amino acids,and peptides of Chinese medicine and result in the loss of efficacy.The far-infrared drying method is suitable for drying thin-layer medicinal materials and is friendly to the environment.Freeze-drying can preserve the active ingredients very well and greatly retain the efficacy,but it has obvious limitations in preserving some Chinese medicinal materials that need to kill enzymes and protect glycosides;besides,the cost is relatively high and the drying time is long.