Celastrol induced the autophagy of spermatogonia cells contributed to tripterygium glycosides-related testicular injury.

Tripterygium glycosides (TG) is extracted from the roots of Chinese herbal medicine named Tripterygium wilfordii Hook F (TwHF). TG tablets are the representative TwHF-based agents with anti-inflammatory and immunomodulatory activities for treating rheumatoid arthritis. Although the curative effect of TG is remarkable, the clinical application is limited by a variety of organ toxicity. One of the most serious side-effects induced by TG is damage of the male reproductive system and the toxic mechanism is still not fully elucidated. TG-induced testicular injury was observed in male mice by treated with different concentrations of TG. The results showed that TG induced a significant decrease in testicular index. Pathological observation showed that spermatogenic cells were obviously shed, arranged loosely, and the spermatogenic epithelium was thin compared with control mice. In addition, the toxic effect of TG on mouse spermatogonia GC-1 cells was investigated. The results displayed that TG induced significant cytotoxicity in mouse GC-1 cells. To explore the potential toxic components that triggered testicular injury, the effects of 8 main components of TG on the viability of GC-1 cells were detected. The results showed that celastrol was the most toxic component of TG to GC-1 cells. Western blot analysis showed that LC3-II and the ratio of LC3-II/LC3-I were significantly increased and the expression level of p62 were decreased in both TG and celastrol treated cells, which indicated the significant activation of autophagy in spermatogonia cells. Therefore, autophagy plays an important role in the testicular injury induced by TG, and inhibition of autophagy is expected to reduce the testicular toxicity of TG.

The pathological mechanisms and potential therapeutic drugs for myocardial ischemia reperfusion injury.

BACKGROUND: Cardiovascular disease is the main cause of death and disability, with myocardial ischemia being the predominant type that poses a significant threat to humans. Reperfusion, an essential therapeutic approach, promptly reinstates blood circulation to the ischemic myocardium and stands as the most efficacious clinical method for myocardial preservation. Nevertheless, the restoration of blood flow associated with this process can potentially induce myocardial ischemia-reperfusion injury (MIRI), thereby diminishing the effectiveness of reperfusion and impacting patient prognosis. Therefore, it is of great significance to prevent and treat MIRI. PURPOSE: MIRI is an important factor affecting the prognosis of patients, and there is no specific in-clinic treatment plan. In this review, we have endeavored to summarize its pathological mechanisms and therapeutic drugs to provide more powerful evidence for clinical application. METHODS: A comprehensive literature review was conducted using PubMed, Web of Science, Embase, Medline and Google Scholar with a core focus on the pathological mechanisms and potential therapeutic drugs of MIRI. RESULTS: Accumulated evidence revealed that oxidative stress, calcium overload, mitochondrial dysfunction, energy metabolism disorder, ferroptosis, inflammatory reaction, endoplasmic reticulum stress, pyroptosis and autophagy regulation have been shown to participate in the process, and that the occurrence and development of MIRI are related to plenty of signaling pathways. Currently, a range of chemical drugs, natural products, and traditional Chinese medicine (TCM) preparations have demonstrated the ability to mitigate MIRI by targeting various mechanisms. CONCLUSIONS: At present, most of the research focuses on animal and cell experiments, and the regulatory mechanisms of each signaling pathway are still unclear. The translation of experimental findings into clinical practice remains incomplete, necessitating further exploration through large-scale, multi-center randomized controlled trials. Given the absence of a specific drug for MIRI, the identification of therapeutic agents to reduce myocardial ischemia is of utmost significance. For the future, it is imperative to enhance our understanding of the pathological mechanism underlying MIRI, continuously investigate and develop novel pharmaceutical agents, expedite the clinical translation of these drugs, and foster innovative approaches that integrate TCM with Western medicine. These efforts will facilitate the emergence of fresh perspectives for the clinical management of MIRI.

Exploring the effective compounds and potential mechanisms of Shengxian Decoction against coronary heart disease by UPLC-Q-TOF/MS and network pharmacology analysis.

As a well-known classical Chinese medicine prescription, Shengxian Decoction (SXD) has been applied for a century to treat cardiovascular diseases, especially coronary heart disease (CHD), but the potentially effective compounds and underlying mechanisms remain unclear. With ultra-performance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-Q-TOF/MS) and network pharmacology analysis, the potential effective compounds of SXD and their pharmacological mechanisms against CHD were identified and revealed. 57 effective compounds with favorable pharmacokinetic characteristics and biological activities were screened through UPLC-Q-TOF/MS analysis, database and literature mining, interacting with 96 CHD-related targets to support potential synergistic therapeutic actions. Systematic analysis of the PPI network and microarray data further revealed six core targets, including TNF, IL-1ß, IL-6, TP53, VEGFA and PTGS2, which were mainly involved in fluid shear stress and atherosclerosis, lipid and atherosclerosis, PI3K-Akt signaling pathway et al. Moreover, the proposed contribution indexes of effective compounds indicated these compounds, including isoferulic acid, quercetin, calycosin, ferulic acid, kaempferol, calycosin 7-O-glycoside, formononetin, astragaloside IV and saikosaponin D, as the core compounds of SXD. The molecular docking results confirmed that those core compound-target pairs exhibited strong binding energy. Furthermore, we validated that SXD significantly alleviated myocardial tissue injury in CHD rats and reversed H/R-induced decreases in H9c2 cell viability by attenuating the production of TNF, IL-6 and IL-1ß, and reducing cardiomyocyte apoptosis via down-regulating the TP53, caspase3 and cytochrome C mRNA expression levels as well as caspase3, caspase9 and cytochrome C protein expression levels according to RT-qPCR and Western blot results. Our findings explained the pharmacological mechanisms underlying the effectiveness of SXD in the treatment of CHD, and laid a foundation for future basic and clinical research of SXD.

The identification of metabolites from gut microbiota in coronary heart disease via network pharmacology.

Although the gut microbial metabolites exhibit potential effects on coronary heart disease (CHD), the underlying mechanism remains unclear. In this study, the active gut microbial metabolites acting on CHD and their potential mechanisms of action were explored through a network pharmacological approach. We collected a total of 208 metabolites from the gutMgene database and 726 overlapping targets from the similarity ensemble approach (SEA) and SwissTargetPrediction (STP) database, and ultimately identified 610 targets relevant to CHD. In conjunction with the gutMGene database, we identified 12 key targets. The targets of exogenous substances were removed, and 10 core targets involved in CHD were eventually retained. The microbiota-metabolites-targets-signalling pathways network analysis revealed that C-type lectin receptor signalling pathway, Lachnospiraceae, Escherichia, mitogen-activated protein kinase 1, prostaglandin-endoperoxidase synthase 2, phenylacetylglutamine and alcoholic acid are notable components of CHD and play important roles in the development of CHD. The results of molecular docking experiments demonstrated that AKT1-glycocholic acid and PTGS2-phenylacetylglutamine complexes may act on C-type lectin receptor signalling pathways. In this study, the key substances and potential mechanisms of gut microbial metabolites were analysed via network pharmacological methods, and a scientific basis and comprehensive idea were provided for the effects of gut microbial metabolites on CHD.

A study integrated metabolomics and network pharmacology to investigate the effects of Shicao in alleviating acute liver injury.

ETHNOPHARMACOLOGICAL RELEVANCE: Shicao is the aerial part of Achillea alpina L., a common herb found mainly in Europe, Asia, and North America. Traditional Chinese medicine has a history of thousands of years and is widely used to treat various diseases. AIM OF STUDY: To explore the hepatoprotective effects of Shicao on CCl4-induced acute liver injury. METHODS: A rat model of acute liver injury was established and liver function indices were assessed to evaluate the protective effect of Shicao on the liver. Untargeted metabolomics of the serum and liver tissues was conducted using UPLC-Q-TOF/MS to identify differential metabolites related to acute liver injury. A network of metabolite-reaction-enzyme-gene constituents was constructed using network pharmacology. Hub targets and key components of the effect of Shicao on acute liver injury were screened from the network. RESULTS: Compared to the model group, Shicao improved the degree of liver damage through the assessment of the liver index, ALT and AST levels, and hepatic pathology slices, demonstrating its hepatoprotective effect against acute liver injury in rats. 10 and 38 differential metabolites involved in acute liver injury were identified in serum and liver tissues, respectively. Most of these were regulated or restored following treatment with Shicao, which mainly consisted of bile acids, lipids, and nucleotides such as taurocholic acid, LysoPC (17:0), and adenosine diphosphate ribose. Through the network of metabolite-reaction-enzyme-gene-constituents, 10 key components and 5 hub genes, along with 7 crucial differential metabolites, were mainly involved in glycerophospholipid metabolism, purine metabolism, biosynthesis of unsaturated fatty acids, and primary bile acid biosynthesis, which may play important roles in the prevention of acute liver injury by Shicao. CONCLUSION: This study revealed that Shicao had protective effects against CCl4-induced liver injury in rats. It was speculated that the ingredients of Shicao might be closely related to the hub targets, thereby regulating the levels of key metabolites, affecting inflammatory response and oxidative stress and attenuate the liver injury consequently. This study provides a basis for further investigation of its therapeutic potential and the mechanism of action.

The effective combination therapies with irinotecan for colorectal cancer.

Colorectal cancer is the third most common type of cancer worldwide and has become one of the major human disease burdens. In clinical practice, the treatment of colorectal cancer has been closely related to the use of irinotecan. Irinotecan combines with many other anticancer drugs and has a broader range of drug combinations. Combination therapy is one of the most important means of improving anti-tumor efficacy and overcoming drug resistance. Reasonable combination therapy can lead to better patient treatment options, and inappropriate combination therapy will increase patient risk. For the colorectal therapeutic field, the significance of combination therapy is to improve the efficacy, reduce the adverse effects, and improve the ease of treatment. Therefore, we explored the clinical advantages of its combination therapy based on mechanism or metabolism and reviewed the rationale basis and its limitations in conducting exploratory clinical trials on irinotecan combination therapy, including the results of clinical trials on the combination potentiation of cytotoxic drugs, targeted agents, and herbal medicine. We hope that these can evoke more efforts to conduct irinotecan in the laboratory for further studies and evaluations, as well as the possibility of more in-depth development in future clinical trials.

Neuroprotection by tetramethylpyrazine and its synthesized analogues for central nervous system diseases: a review.

BACKGROUND: Due to the global increase in aging populations and changes in modern lifestyles, the prevalence of neurodegenerative diseases, cerebrovascular disorders, neuropsychiatrcic conditions, and related ailments is rising, placing an increasing burden on the global public health system. MATERIALS AND METHODS: All studies on tetramethylpyrazine (TMP) and its derivatives were obtained from reputable sources such as PubMed, Elsevier, Library Genesis, and Google Scholar. Comprehensive data on TMP and its derivatives was meticulously compiled. RESULTS: This comprehensive analysis explains the neuroprotective effects demonstrated by TMP and its derivatives in diseases of the central nervous system. These compounds exert their influence on various targets and signaling pathways, playing crucial roles in the development of various central nervous system diseases. Their multifaceted mechanisms include inhibiting oxidative damage, inflammation, cell apoptosis, calcium overload, glutamate excitotoxicity, and acetylcholinesterase activity. CONCLUSION: This review provides a brief summary of the most recent advancements in research on TMP and its derivatives in the context of central nervous system diseases. It involves synthesizing analogs of TMP and evaluating their effectiveness in models of central nervous system diseases. The ultimate goal is to facilitate the practical application of TMP and its derivatives in the future treatment of central nervous system diseases.

Chemical Composition, Pharmacological Effects and Clinical Applications of Cinobufacini.

Chinese medicine cinobufacini is an extract from the dried skin of Bufo bufo gargarizans Cantor, with active ingredients of bufadienolides and indole alkaloids. With further research and clinical applications, it is found that cinobufacini alone or in combination with other therapeutic methods can play an anti-tumor role by controlling proliferation of tumor cells, promoting apoptosis, inhibiting formation of tumor neovascularization, reversing multidrug resistance, and regulating immune response; it also has the functions of relieving cancer pain and regulating immune function. In this paper, the chemical composition, pharmacological effects, clinical applications, and adverse reactions of cinobufacini are summarized. However, the extraction of monomer components of cinobufacini, the relationship between different mechanisms, and the causes of adverse reactions need to be further studied. Also, high-quality clinical studies should be conducted.

[Identification of quality markers of Gei Herba based on analytic hierarchy process-entropy weight method and network pharmacology].

Analytic hierarchy process(AHP)-entropy weight method(EWM) and network pharmacology were employed to identify the potential quality markers(Q-markers) of Gei Herba. According to the new concept of Q-markers in traditional Chinese medicine(TCM), the AHP-EWM was applied to quantitatively identify the Q-markers of Gei Herba. The AHP was used for the weight analysis of primary indicators(factor layer), and the EWM for the analysis of literature and experimental data of secondary indicators(control layer). In addition, network pharmacology was employed to build the "component-target-disease-efficacy" network for Gei Herba, and the components showing strong associations with the Qi-replenishing, spleen-invigorating, blood-tonifying, Yin-nourishing, lung-moistening, and phlegm-resolving effects of Gei Herba were screened out. According to the results of AHP-EWM and network pharmacology, four components, i.e., ellagic acid, gallic acid, gemin G, and gemin C, were finally identified as potential Q-markers of Gei Herba. In this study, the AHP-EWM and network pharmacology were employed to screen the Q-markers of Gei Herba, which provided ideas for the quantitative evaluation and identification of Q-markers of TCM.

Research Progress on Flavor and Quality of Chinese Rice Wine in the Brewing Process.

Chinese rice wine (CRW) is a traditional and unique alcoholic beverage in China, favored by many consumers for its rich aroma, unique taste, and complex ingredients. Its flavor is primarily composed of volatile and nonvolatile compounds. These flavor compounds are partly derived from grains and starters (Qu), while the other part is produced by microbial metabolism and chemical reactions during the brewing process. Additionally, ethyl carbamate (EC) in CRW, a hazardous chemical, necessitates controlling its concentration during brewing. In recent years, numerous new brewing techniques for CRW have emerged. Therefore, this paper aims to collect aroma descriptions and thresholds of flavor compounds in CRW, summarize the relationship between the brewing process of CRW and flavor formation, outline methods for reducing the concentration of EC in the brewing process of CRW, and summarize the four stages (pretreatment of grains, fermentation, sterilization, and aging process) of new techniques. Furthermore, we will compare the advantages and disadvantages of different approaches, with the expectation of providing a valuable reference for improving the quality of CRW.

The serum lipidomics reveal the action mechanism of Danggui-Yimucao herbal pair in abortion mice.

Medical abortion is a common medical procedure that women choose to terminate an unwanted pregnancy, but it often brings post-abortion complications. Danggui (Angelica sinensis Radix)-Yimucao (Leonuri Herba), as a herbal pair (DY) in clinical prescriptions of traditional Chinese medicine, is often used in the treatment of gynecological diseases and has the traditional functions of tonifying the blood, promoting blood circulation, removing blood stasis and regulating menstruation. In this study, serum lipidomics were adopted to dissect the mechanism of DY in promoting recovery after medical abortion. A total of 152 differential metabolites were screened by lipidomics. All metabolites were imported into MetaboAnalyst for analysis, and finally key metabolic pathways such as glycerophospholipid metabolism, linoleic acid metabolism and pentose and glucuronate interconversions were enriched. Our results indicated that metabolic disorders in abortion mice were alleviated by DY through glycerophospholipid metabolism, while prostaglandin and leukotriene metabolites might be the key targets of DY to promote post-abortion recovery.

Recent advances in the pharmacological applications and liver toxicity of triptolide.

Triptolide is a predominant active component of Triptergium wilfordii Hook. F, which has been used for the treatment of cancers and autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus and diabetic nephropathy. Therefore, triptolide and its derivates are considered to have promising prospects for development into drugs. However, the clinical application of triptolide is limited due to various organ toxicities, especially liver toxicity. The potential mechanism of triptolide-induced hepatotoxicity has attracted increasing attention. Over the past five years, studies have revealed that triptolide-induced liver toxicity is involved in metabolic imbalance, oxidative stress, inflammations, autophagy, apoptosis, and the regulation of cytochrome P450 (CYP450) enzymes, gut microbiota and immune cells. In this review, we summarize the pharmacological applications and hepatotoxicity mechanism of triptolide, which will provide solid theoretical evidence for further research of triptolide.

Time-dependent laxative effect of sennoside A, the core functional component of rhubarb, is attributed to gut microbiota and aquaporins.

ETHNOPHARMACOLOGICAL RELEVANCE: Sennoside A is a natural anthraquinone component mainly derived from rhubarb and has been routinely used as a clinical stimulant laxative. However, long-term application of sennoside A may lead to drug resistance and even adverse reactions, thus limiting its clinical use. Therefore, to reveal the time-dependent laxative effect and potential mechanism of sennoside A is of critical importance. AIM OF THE STUDY: This study was conducted to investigate the time-dependent laxative effect of sennoside A and unveil its underlying mechanism from the perspective of gut microbiota and aquaporins (AQPs). MATERIALS AND METHODS: Based on a mouse constipation model, 2.6 mg/kg sennoside A was administered orally for 1, 3, 7, 14 and 21 days, respectively. The laxative effect was assessed by the fecal index and fecal water content, the histopathology of the small intestine and colon was evaluated by hematoxylin-eosin staining. Gut microbiota changes was observed by 16S rDNA sequencing, and colonic AQPs expression was analyzed by quantitative real-time polymerase chain reaction and western blotting. Partial least-squares regression (PLSR) was used to screen out the effective indicators contributing to the laxative effect of sennoside A. The effective indicators were then fitted to time by a drug-time curve model to analyze the trend of efficacy of sennoside A, and the optimal time of administration was derived by comprehensive analysis with a three-dimensional (3D) time-effect image. RESULTS: Sennoside A had a significant laxative effect at 7 days of administration with no pathological changes in the small intestine or colon; however, at 14 or 21 days of administration, the laxative effect diminished and slight damage to the colon was observed. Sennoside A affects the structure and function of gut microbes. The alpha diversity showed that the abundance and diversity of gut microorganisms reached the highest value after 7 days of administration. Partial least squares discriminant analysis showed that the composition of the flora was close to normal when administered for less than 7 days, but was closest to the composition of constipation over 7 days. The expression of aquaporin 3 (AQP3) and aquaporin 7 (AQP7) decreased gradually after the administration of sennoside A, with the lowest expression at 7 days, and then increased gradually afterwards, while the expression of aquaporin 1 (AQP1) was the opposite. The PLSR results showed that AQP1, AQP3, Lactobacillus, Romboutsia, Akkermansia and UCG_005 contributed more to the laxative effect of the fecal index, and after fitting with the drug-time curve model, each index showed a trend of increasing and then decreasing. The comprehensive evaluation of the 3D time-effect image concluded that the laxative effect of sennoside A reached its best after 7 days of administration. CONCLUSION: Sennoside A should be used in regular dosages for less than one week, as it provides significant relief of constipation and exhibits no colonic damage within 7 days of administration. In addition, Sennoside A exerts its laxative effect by regulating gut microbiota of Lactobacillus Romboutsia, Akkermansia and UCG_005 and water channels of AQP1 and AQP3.

Potential Medicinal Value of Rhein for Diabetic Kidney Disease.

Diabetic kidney disease (DKD) is the primary cause of mortality among diabetic patients. With the increasing prevalence of diabetes, it has become a major concern around the world. The therapeutic effect of clinical use of drugs is far from expected, and therapy choices to slow the progression of DKD remain restricted. Therefore, research on new drugs and treatments for DKD has been a hot topic in the medical field. It has been found that rhein has the potential to target the pathogenesis of DKD and has a wide range of pharmacological effects on DKD, such as anti-nephritis, decreasing blood glucose, controlling blood lipids and renal protection. In recent years, the medical value of rhein in the treatment of diabetes, DKD and renal disease has gradually attracted worldwide attention, especially its potential in the treatment of DKD. Currently, DKD can only be treated with medications from a single symptom and are accompanied by adverse effects, while rhein improves DKD with a multi-pathway and multi-target approach. Therefore, this paper reviews the therapeutic effects of rhein on DKD, and proposes solutions to the limitations of rhein itself, in order to provide valuable references for the clinical application of rhein in DKD and the development of new drugs.

A three-dimensional integration strategy for Q-markers identification: Taken Euphorbia Pekinensis Radix as an example.

Euphorbia Pekinensis Radix (EPR) is an important antitumor medicinal resource. However, quality control of EPR has not been well established due to the lack of quality markers (Q-markers) research. In this study, a three-dimensional integration strategy was developed to systematically characterize Q-markers and this method was successfully applied to identify Q-markers of EPR. Firstly, three core quality attributes-effectiveness, testability and specificity-were considered as three dimensions, and the weights of each dimension were calculated by analytical hierarch process. Then, the values of each dimension were evaluated by multi-indicators. For EPR with antitumor activity, cytotoxic assay and network pharmacology, UPLC analysis and literature search, compound belonging search were employed to calculate the values of effectiveness, testability and specificity, respectively. Finally, the weights and values were multiplied as the scores of each component on that dimension, and the total scores of the three dimensions were further integrated based on the radar plot and expressed as regression area, by which Q-markers were quantified and visualized. Five components were identified as Q-markers of EPR due to their high-ranked antitumor capacity, ease of measurement and excellent specificity, which laid an important foundation for the quality control improvement of EPR. Furthermore, the integrated strategy summarized here is helpful for the quantitative identification of Q-markers and promote the quality standard of traditional Chinese medicine.

[Quantitative identification of Q-markers of Euphorbiae Humifusae Herba based on AHP-CRITIC comprehensive weighting method].

This study investigated the quality markers(Q-markers) of Euphorbiae Humifusae Herba based on the analytic hierarchy process(AHP)-criteria importance through intercriteria correlation(CRITIC) comprehensive weighting method. The Q-markers evaluation system was constructed based on the AHP-CRITIC comprehensive weighting method with quantitative identification of Q-markers of Euphorbiae Humifusae Herba as the target layer. The index weights of the factor layer and the control layer were integrated based on the weights of three indicators(effectiveness, testability, and specificity) in the factor layer calculated by the AHP method and weights of eight indicators(anti-inflammatory inhibitory rate, coagulation shortening rate, anti-cancer inhibition rate, component degree value, component test batch, component average content, content variation coefficient, and number of medicinal materials retrieved according to components) in the control layer calculated by the CRITIC method. The comprehensive score of the chemical components of Euphorbiae Humifusae Herba was weighted and ranked to identify the Q-markers of Euphorbiae Humifusae Herba. In terms of comprehensive scores, top 10 potential Q-markers of Euphorbiae Humifusae Herba were ranked as cynaroside > quercetin > gallic acid > apigenin > luteolin > apigenin-7-O-glucoside > quercetin-7-O-glucoside > ellagic acid > astragalin > ethyl gallate. This study provides a reference for the quality control of Euphorbiae Humifusae Herba and a methodological reference for the quantitative identification of Q-markers of Chinese medicine.

Integrated dose-response metabolomics with therapeutic effects and adverse reactions may demystify the dosage of traditional Chinese medicine.

BACKGROUND: Traditional Chinese medicine (TCM) has been used to treat various diseases for thousands of years. However, the uncertainty of dosage as well as the lack of systemic evaluation of pharmacology and toxicology is one major reason why TCM remains mysterious and is not accepted worldwide. Hence, we aimed to propose an integrated dose-response metabolomics strategy based on both therapeutic effects and adverse reactions to guide the TCM dosage in treatment. METHODS: The proposed methodology of integrated dose-response metabolomics includes four steps: dose design, multiple comparison of metabolic features, response calculation and dose-response curve fitting. By comparing the changes of all metabolites under different doses and calculating these changes through superposition, it is possible to characterize the global disturbance and thus describe the overall effect and toxicity of TCM induced by different doses. Rhubarb, commonly used for constipation treatment, was selected as a representative TCM. RESULTS: This developed strategy was successfully applied to rhubarb. The dose-response curves clearly showed the efficacy and adverse reactions of rhubarb at different doses. The rhubarb dose of 0.69 g/kg (corresponding to 7.66 g in clinic) was selected as the optimal dose because it was 90% of the effective dose and three adverse reactions were acceptable in this case. CONCLUSION: An integrated dose-response metabolomics strategy reflecting both therapeutic effects and adverse reactions was established for the first time, which we believe is helpful to uncover the mysterious veil of TCM dosage. In addition, this strategy benefits the modernization and internationalization of TCM, and broadens the application of metabolomics.

Are Older People Really More Susceptible to SARS-CoV-2?

Since the outbreak, COVID-19 has spread rapidly across the globe due to its high infectivity and lethality. Age appears to be one of the key factors influencing the status and progression of SARS-CoV-2 infection, as multiple reports indicated that the majority of COVID-19 infections and severe cases are elderly. Most people simply assume that the elderly are more susceptible to SARS-CoV-2 than the young, but the mechanism behind it is still open to question. The older and younger people are at similar risk of infection because their infection process is the same and they must be exposed to the virus first. However, whether they will get sick after exposure to the virus and how their disease progresses depend on their immune mechanisms. In older populations, inflammation and immune aging reduce their ability to resist SARS-CoV-2 infection. Meanwhile, under the influence of comorbidities, ACE2 receptor and various cytokines undergo corresponding changes, thus accelerating the entry, replication, and transmission of SARS-CoV-2 in the body, promoting disease progression, and leading to severe illness and even death. In addition, the relatively fragile mental state of the elderly can also affect their timely recovery from COVID-19. Therefore, once older people are infected with SARS-CoV-2, they are more prone to severe illness and death with a poor prognosis, and they should strengthen protection to avoid exposure to the virus.