Mechanism of the different metabolome responses between Plutella xylostella and Pieris rapae treated with the diamide insecticides

Diamide insecticides, such as chlorantraniliprole, cyantraniliprole, and tetrachlorantraniliprole, are a new class of insecticides that selectively target insects by affecting calcium homeostasis. While this class of insecticides are effective on a wide range of insect pests, the toxicities of diamide insecticides vary among species and life stages. In this study, we addressed the mechanism underlying the different responses of Plutella xylostella and Pieris rapae to diamide insecticides. The susceptibility to insecticides of P. xylostella and P. rapae larvae was assessed 2 and 4 days after exposure to chlorantraniliprole, cyantraniliprole, and tetrachlorantraniliprole. P. xylostella larvae treated with distilled water (Group A), chlorantraniliprole (Group B), cyantraniliprole (Group C), and tetrachlorantraniliprole (Group D) and P. rapae larvae treated with distilled water (Group E), chlorantraniliprole (Group F), cyantraniliprole (Group G) and tetrachlorantraniliprole (Group H) were subjected to metabolomics analysis. The differential metabolites in the B vs. F, C vs. G, and D vs. H groups were analyzed, followed by pathway enrichment analysis. Chlorantraniliprole, cyantraniliprole, and tetrachlorantraniliprole all showed high toxicities for P. xylostella and P. rapae larvae. P. rapae larvae were more sensitive to the diamide insecticides than P. xylostella larvae. There were 65 overlapped differential metabolites between P. xylostella and P. rapae larvae treated with these three diamide insecticides. Pathway analysis showed that the differential metabolites were closely related with fatty acid biosynthesis and metabolism-related pathways. The differential regulation of fatty acid biosynthesis and metabolism may contribute to the different response to diamide insecticides in P. xylostella and P. rapae.

Propranolol regulates ERK1/2 signaling pathway and promotes chronic wound healing in diabetic rats

OBJECTIVE

This study aimed to investigate if propranolol could regulate ERK1/2 signaling pathway and promote chronic wound healing in diabetic rats.

MATERIALS AND METHODS

Twenty-two rats were used to establish a diabetic chronic wound animal model. They were randomly separated into two groups: the propranolol group and the control group. The propranolol group was treated with propranolol ointment and the control group was treated with propranolol matrix cream to cover the wound surface. The expression of the p-ERK1/2 protein was detected by the Western Blot. RT-qPCR was used to detect the expression of VEGF. The concentrations of IL-6 and TNF-α were detected by ELISA.

RESULTS

The body weight of rats was significantly reduced after type 2 diabetes mellitus modeling. The healing rate of rats in the control group was significantly lower than that in the propranolol group (p<0.05). There was a significant increase in the expression of the p-ERK1/2 protein in the wound tissue of the propranolol group compared with that in the control group, except for the 11th day (p<0.05). The relative expression of Vascular Endothelial Growth Factor (VEGF) in the propranolol group was significantly higher than that in the control group on the 2nd day (p<0.05), while the relative expression of VEGF in the propranolol group was significantly increased on the 11th day after modeling (p<0.05). On the 20th day, the expressions of IL-6 and TNF-α in the propranolol group were significantly higher than those in the control group, and there were significant differences (p<0.05). It was found that the IL-6 and TNF-α expressions in the propranolol group reached the peak on the 11th day and then gradually decreased (p<0.05).

CONCLUSIONS

The results indicated that propranolol can accelerate the healing of diabetic wounds by regulating the expression of VEGF by phosphorylation of ERK1/2 protein, thus promoting chronic wound healing in diabetes.

Identification of Colletotrichum Species Associated with Blueberry Anthracnose in Sichuan, China

Anthracnose caused by Colletotrichum spp. is an important disease of blueberries and results in large economic losses for blueberry growers. Samples of anthracnose were collected from six main blueberry cultivation areas in Sichuan Province. In total, 74 Colletotrichum isolates were obtained through a single-spore purification method and identified to the species through morphological characteristics and phylogenetic analyses based on partial DNA sequences of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), internal transcribed spacer (ITS) regions, and the β-tubulin (TUB2), actin (ACT) and calmodulin (CAL) genes. Among all species, Colletotrichum fructicola was the most dominant species, with an isolation percentage of up to 66.2% in Sichuan, followed by Colletotrichum siamense (17.6%), C. kahawae (5.4%), C. karstii (5.4%), C. nymphaeae (2.7%) and C. sichuaninese (2.7%). Pathogenicity tests showed all species were able to cause typical anthracnose symptoms on blueberry leaves and stems. Colletotrichum fructicola was the predominant species with strong aggressiveness. Moreover, C. fructicola, C. kahawae, C. sichuaninese and C. nymphaeae are first reported here to cause blueberry anthracnose. This study provides a comprehensive reference for the association of different Colletotrichum spp., which may support the sustainable management of blueberry anthracnose.

Potential Role of Photosynthesis in the Regulation of Reactive Oxygen Species and Defence Responses to Blumeria graminis f. sp. tritici in Wheat

Photosynthesis is not only a primary generator of reactive oxygen species (ROS) but also a component of plant defence. To determine the relationships among photosynthesis, ROS, and defence responses to powdery mildew in wheat, we compared the responses of the Pm40-expressing wheat line L658 and its susceptible sister line L958 at 0, 6, 12, 24, 48, and 72 h post-inoculation (hpi) with powdery mildew via analyses of transcriptomes, cytology, antioxidant activities, photosynthesis, and chlorophyll fluorescence parameters. The results showed that H₂O₂ accumulation in L658 was significantly greater than that in L958 at 6 and 48 hpi, and the enzymes activity and transcripts expression of peroxidase and catalase were suppressed in L658 compared with L958. In addition, the inhibition of photosynthesis in L658 paralleled the global downregulation of photosynthesis-related genes. Furthermore, the expression of the salicylic acid-related genes non-expressor of pathogenesis related genes 1 (NPR1), pathogenesis-related 1 (PR1), and pathogenesis-related 5 (PR5) was upregulated, while the expression of jasmonic acid- and ethylene-related genes was inhibited in L658 compared with L958. In conclusion, the downregulation of photosynthesis-related genes likely led to a decline in photosynthesis, which may be combined with the inhibition of peroxidase (POD) and catalase (CAT) to generate two stages of H₂O₂ accumulation. The high level of H₂O_2, salicylic acid and PR1 and PR5 in L658 possible initiated the hypersensitive response.

Influence of roflumilast on sepsis mice through the JAK/STAT signaling pathway

OBJECTIVE

The aim of this study was to explore the influence of roflumilast on sepsis mice through the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway.

MATERIALS AND METHODS

A total of 36 Sprague-Dawley mice were randomly divided into normal group (n=12), model group (n=12) and roflumilast group (n=12). Mice in the normal group were fed normally. However, mice in the model group and roflumilast group were intraperitoneally injected with endotoxin to establish the sepsis mouse model. Furthermore, mice in the model group and roflumilast group were intraperitoneally injected with 0.9% sodium chloride and roflumilast once a day, respectively. After 7 d of intervention, mice were sampled. Lung tissue morphology was observed via hematoxylin-eosin (HE) staining, and the pathological score was given. The protein expression levels of JAK and STAT-3 were detected via Western blotting. The expression levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were detected via enzyme-linked immunosorbent assay (ELISA). Meanwhile, the mRNA expression levels of JAK, STAT-3, IL-6 and TNF-α were detected via quantitative Polymerase Chain Reaction (qPCR). The number of inflammatory cells in the lavage fluid was counted by a biochemical detector.

RESULTS

The survival rate of mice in the roflumilast group was significantly higher than that of the model group (p<0.05). The results of HE staining revealed that lung tissue morphology in roflumilast group was significantly improved when compared with the model group. Meanwhile, the pathological score in the roflumilast group was significantly lower than that of the model group (p<0.05). Western blotting showed that the protein expression levels of JAK and STAT-3 in the roflumilast group were markedly lower than those of the model group (p<0.05). According to the results of ELISA, the expression levels of IL-6 and TNF-α in the roflumilast group were remarkably lower than the model group (p<0.05). Further qPCR results manifested that the mRNA expression levels of JAK, STAT-3, IL-6 and TNF-α in the roflumilast group were significantly lower than those of the model group (p<0.05). Moreover, the number of neutrophils, monocytes and lymphocytes in the roflumilast group was significantly smaller than the model group.

CONCLUSIONS

Roflumilast can improve lung tissue morphology of sepsis mice by inhibiting the JAK/STAT signaling pathway.

Diversity of the Seedborne Fungi and Pathogenicity of Fusarium Species Associated with Intercropped Soybean

Maize/soybean relay strip intercropping has been widely practiced in Southwest China due to its high productivity and effective application of agricultural resources; however, several seedborne diseases such as seedling blight, pod and seed decay are frequently observed causing severe yield loss and low seed quality. So far, the population and pathogenicity of the seedborne fungi associated with intercropped soybean remain unexplored. In this study, seeds of 12 soybean cultivars screened for intercropping were collected from three growing regions in Sichuan Province of Southwest China, and the seedborne fungi were isolated from the surface-sterilized seeds. Based on sequence analysis of ribosomal DNA internal transcribed spacer (rDNA ITS), 148 isolates were identified into 13 fungal genera, among which Fusarium covered 55.0% as the biggest population followed by Colletotrichum. Furthermore, Fusarium isolates were classified into five distinct species comprising F. fujikuroi, F. proliferatum, F. verticillioides, F. asiaticum and F. incarnatum through sequence analysis of translation elongation factor 1 alpha (EF-1α) and DNA-directed RNA ploymerase II second largest subunit (RPB2). Among them, F. fujikuroi accounted for 51.22% (42/82) and was isolated from 91.7% (11/12) soybean varieties. Pathogenicity assay showed that five Fusarium species were able to infect the seeds of soybean cultivar “Nandou12” and caused water-soaked or rot symptoms, while F. fujikuroi and F. asiaticum had much higher aggressiveness than other species with significant reductions of seed fresh weight and germination percentage. Accordingly, this study indicates that Fusarium species are the dominant seedborne fungi in the intercropped soybean in Sichuan, China, and this provides some useful references for the effective management of seedborne fungal diseases as well as soybean resistance breeding in maize/soybean relay strip intercropping.

Effects of ghrelin on the electrical activities of substantia nigra dopaminergic neurons treated with MPP

Ghrelin, a 28 amino acid brain-gut peptide, has attracted increasing attention for its neuroprotective effect in Parkinson's disease (PD). In view of the pivotal role of excitability of dopaminergic neurons in substantia nigra pars compacta (SNc) in the function of nigrostriatal system, it is of great significance to elucidate the regulation of electrical activity of dopaminergic neurons by ghrelin, especially in PD pathogenesis. In this study, we tackled this issue by probing the effects of ghrelin on the electrophysiological properties of dopaminergic neurons in acute application of Methyl-4-phenylpyridinium (MPP⁺), a potent parkinsonizing agent in primates and rodents, with whole cell patch clamp technique. We first observed that MPP⁺ (10, 20 and 50 μM) inhibited the spontaneous firing activity of dopaminergic neurons with dose-dependent and time-dependent properties. MPP⁺ also hyperpolarized the membrane potential, inhibited the evoked firing activity and reduced the amplitude of the inward rectification characteristic (Sag) in dopaminergic neurons. Importantly, ghrelin (100 nM) could improve the above effects of MPP⁺ on the electrical activities of dopaminergic neurons. The potential mechanism of this phenomenon may be that ghrelin upregulated hyperpolarization-activated cyclic nucleotide-gated channel current (I_h) to antagonize the inhibition of MPP⁺ on I_h, thereby improving the electrical activities of dopaminergic neurons.

Evaluation of serum cytokines to predict serofast in syphilis patients

BACKGROUND

Syphilis serofast has been increasing in recent years and has resulted in a dramatic increase in medical expenses. However, there are not effective methods for serofast prediction in syphilis patients prior to treatment.

AIMS AND OBJECTIVES

The present study investigated novel serum biomarkers for the prediction of serofast in syphilis patients prior to treatment.

MATERIALS AND METHODS

Pre-treatment serum from patients with syphilis serofast and patients with syphilis serological cure were measured using antibody microarrays. The results generated from the antibody arrays were validated using ELISA. Healthy subjects were used as the controls.

RESULTS

Compared to serologically cured patients, six cytokines (IL-17F, TNF RI, TNF RII, IL-16, OPN, and MCSFR) were significantly lower, while five factors (MCP-3, LIF, G-CSF, MIP-3a, and GH) were higher in serofast patients. ELISA validation was in-line with the results generated from antibody arrays. Of significance, these cytokines were firstly observed to the differentially expressed in pre-treatment serofast patient serum samples.

CONCLUSIONS

The differentially expressed cytokines may be novel serum biomarkers for serofast prediction. These identified proteins play significant roles in the immune response, suggesting immune dysfunction may be the cause for syphilis serofast.

Maize/Soybean Relay Strip Intercropping Reduces the Occurrence of Fusarium Root Rot and Changes the Diversity of the Pathogenic Fusarium Species

Fusarium species are the most detrimental pathogens of soybean root rot worldwide, causing large loss in soybean production. Maize/soybean relay strip intercropping has significant advantages on the increase of crop yields and efficient use of agricultural resources, but its effects on the occurrence and pathogen population of soybean root rot are rarely known. In this study, root rot was investigated in the fields of the continuous maize/soybean strip relay intercropping and soybean monoculture. Fusarium species were isolated from diseased soybean roots and identified based on sequence analysis of translation elongation factor 1α (EF-1α) and RNA polymerase II second largest subunit (RPB2), and the diversity and pathogenicity of these species were also analyzed. Our results showed that intercropping significantly decreased soybean root rot over monoculture. A more diverse Fusarium population including Fusarium solani species complex (FSSC), F. incarnatum-equiseti species complex (FIESC), F. oxysporum, F. fujikuroi, F. proliferatum and F. verticillioides, F. graminearum and F. asiaticum was identified from intercropping while FSSC, FIESC, F. oxysporum, F. commune, F. asiaticum and F. meridionale were found from monoculture. All Fusarium species caused soybean root infection but exhibited distinct aggressiveness. The most aggressive F. oxysporum was more frequently isolated in monoculture than intercropping. FSSC and FIESC were the dominant species complex and differed in their aggressiveness. Additionally, F. fujikuroi, F. proliferatum and F. verticillioides were specifically identified from intercropping with weak or middle aggressiveness. Except for F. graminearum, F. meridionale and F. asiaticum were firstly reported to cause soybean root rot in China. This study indicates maize/soybean relay strip intercropping can reduce soybean root rot, change the diversity and aggressiveness of Fusarium species, which provides an important reference for effective management of this disease.

Rapid isolation of non-aflatoxigenic Aspergillus flavus strains

In the present study, a method for screening non-aflatoxigenic Aspergillus flavus in soil samples collected from major peanut-growing regions of China was developed. The single colonies were picked and cultured on Aspergillus flavus and parasiticus agar (AFPA). If the reverse side of the colony on AFPA was orange-coloured, it was considered A. flavus or Aspergillus parasiticus. After the genomic DNA of each strain was extracted, 28S rRNA and calmodulin were amplified and sequenced to determine the species. The key gene, aflR, was amplified and digested via polymerase chain reaction-restriction fragment length polymorphism. The aflatoxigenic A. flavus and the non-aflatoxigenic A. flavus and A. parasiticus were distinguished by enzyme digestion of aflR. 156 strains of A. flavus were screened, which consisted of 135 aflatoxigenic and 21 non-aflatoxigenic strains. The aflatoxin producing ability of each strain was confirmed using solid-state fermentation experiments. Using the method developed in the present study, we confirmed that the non-aflatoxigenic A. flavus strains isolated lost their capacity to produce aflatoxins. Considering there could be some alterations in other functional genes, some non-aflatoxigenic strains could be identified inaccurately as aflatoxigenic strains, although that did not occur in the present study. The growth of non-aflatoxigenic A. flavus was observed, and the most rapidly growing non-aflatoxigenic strain was selected for plate confrontation assays and toxic mixed culture experiments. The inhibition rate of non-aflatoxigenic A. flavus against aflatoxigenic A. flavus was 55.4 and 72.6% in potato dextrose agar (PDA) plate and natural soybean medium, respectively. The screened non-aflatoxigenic A. flavus strains provide a microbial resource for biological control of aflatoxin contamination.

Mutation spectrum of COL1A1/COL1A2 screening by high-resolution melting analysis of Chinese patients with osteogenesis imperfecta

High-resolution melting (HRM) analysis has been shown to be a time-saving method for the screening of genetic variants. To increase the precision of the diagnosis of osteogenesis imperfecta (OI), we used HRM to explore COL1A1/COL1A2 mutations in 87 Chinese OI patients and to perform population-based studies of the relationships between their genotypes and phenotypes. Peripheral blood samples were collected from the 87 non-consanguineous probands. The coding regions and exon boundaries of COL1A1/COL1A2 were detected by HRM and confirmed by Sanger sequencing. The functional effects of mutations were predicted through bioinformatic tools. Mutations were detected in 70.3% of familial cases and 40% of sporadic cases (p < 0.01). Compared with COL1A1 mutations, patients with COL1A2 mutations were more prone to severe phenotypes. Helical mutations (caused by substitution of the glycine within the Gly-X-Y triplet domain) were more likely to occur in patients with type III and IV (p < 0.05). Haploinsufficiency mutations (caused by frameshift, nonsense, and splice-site mutations) appeared more frequently in patients with type I (p < 0.05). Compared with the Sanger sequencing and whole exome sequencing (WES), HRM was found to reduce total costs by 78%- 80% in patients who had a positive HRM separate melting curve. Our findings suggest that HRM would greatly benefit small and understaffed hospitals and laboratories, and would facilitate the accurate diagnosis and early treatment of OI in remote and less developed regions.

Characterization and Pathogenicity of Fusarium Species Associated with Soybean Pods in Maize/Soybean Strip Intercropping

Intercropping has been considered as a kind of a sustainable agricultural cropping system. In southwest China, maize/soybean strip intercropping has commonly been practised under local limited agricultural land resources. However, heavy rainfall in combination with high humidity and low temperatures cause severe pod and seed deterioration in the maturity and pre-harvesting stages of intercropped soybean. Numerous Fusarium species have been reported as the dominant pathogens of soybean root rot, seedling blight, as well as pod field mold in this area. However, the diversity and pathogenicity of Fusarium species on soybean pods remain unclear. In the current study, diseased soybean pods were collected during the cropping season of 2018 from five different intercropped soybean producing areas. A total of 83 Fusarium isolates were isolated and identified as F. fujikuroi, F. graminearum, F. proliferatum, and F. incarnatum-equiseti species complex based on morphological characteristics and phylogenetic analysis of the nucleotide sequence of EF1-α and RPB2 genes. Pathogenicity tests demonstrated that all Fusarium species were pathogenic to seeds of the intercropped soybean cultivar Nandou12. Fusarium fujikuroi had the maximum disease severity, with a significant reduction of seed germination rate, root length, and seed weight, followed by F. equiseti, F. graminearum, F. proliferatum, and F. incarnatum. Additionally, the diversity of Fusarium species on soybean pods was also considerably distinct according to the geographical origin and soybean varieties. Thus, the findings of the current study will be helpful for the management and resistance breeding of soybean pod decay in the maize/soybean intercropping system.

Compounds from the root of Pueraria peduncularis (Grah. ex Benth.) Benth. and their antimicrobial effects

BACKGROUND

Pueraria peduncularis belongs to the genus Pueraria DC, and has a wide range of medical and agricultural activities. Previous studies have shown that P. peduncularis extracts have broad bioactivities against phytopathogens. In this paper, we systematically studied the fungicidal activity of root methanol extracts and further isolated the active compounds.

RESULTS

The root methanol extract inhibited the mycelial growth of the five tested phytopathogens to different degrees. Among these phytopathogens, the inhibitory effect was greatest against R. solani, with an EC₅₀ value of 324.72 mg L^-1 . Eight compounds were subsequently isolated and identified from P. peduncularis. Among them, puercarpan A and medicarpin showed strong fungicidal activity, with MIC values against Rhizoctonia solani of 1.6 and 6.25 mg L^-1 , respectively. Puercarpan A is a new compound, and its structure was established as (6aR,6bS,11aR)-6b-hydroxy-3-methoxypterocarpan-10-ene-7-one.

CONCLUSION

The P. peduncularis extracts exhibit high antimicrobial activity against R. solani and have great potential value of P. peduncularis as a fungicide. © 2019 Society of Chemical Industry.

Downregulation of kynureninase restrains cutaneous squamous cell carcinoma proliferation and represses the PI3K/AKT pathway

BACKGROUND

The protein kynureninase (KYNU) has recently been reported to participate in the pathological processes of various diseases.

AIM

To explore the expression and the biological function of KYNU in cutaneous squamous cell carcinoma (cSCC).

METHODS

Expression of KYNU in cSCC cell lines and tissues was firstly evaluated based on the Gene Expression Omnibus and the Oncomine databases. Quantitative reverse transcription-PCR was performed to determine the mRNA expression of KYNU in cSCC cell lines. Small interfering RNA (siRNA) was used for silencing KYNU. The effect of KYNU on the growth and motility of cSCC cells was determined by cell counting kit-8, wound-healing and Transwell assays, and western blotting was used to determine the protein expression of KYNU, AKT, phosphoinositide 3-kinase (PI3K), phosphorylated (p)-AKT and p-PI3K.

RESULTS

KYNU was significantly upregulated in cSCC tissues and cell lines. Knockdown of KYNU using siRNA noticeably suppressed the proliferation, migration and invasion ability of SCL-1 cells (P < 0.01). Western blotting revealed that phosphorylation of AKT and PI3K was markedly inhibited after silencing KYNU. The ratios of p-AKT/AKT and p-PI3K/PI3K were significantly decreased in the si-KYNU group compared with the control group.

CONCLUSION

Depletion of KYNU could inhibit the growth of cSCC cells, possibly through modulating PI3K/AKT pathway. These data indicate that KYNU takes a key part in the malignant progression of cSCC, and could be considered as a promising therapeutic target for cSCC treatment.

Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels: An Emerging Role in Neurodegenerative Diseases

Neurodegenerative diseases such as Parkinson's disease (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and spinal muscular atrophy (SMA) are chronic, progressive, and age-associated neurological disorders characterized by neuronal deterioration in specific brain regions. Although the specific pathological mechanisms underlying these disorders have remained elusive, ion channel dysfunction has become increasingly accepted as a potential mechanism for neurodegenerative diseases. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are encoded by the HCN1-4 gene family and conduct the hyperpolarization-activated current (I h). These channels play important roles in modulating cellular excitability, rhythmic activity, dendritic integration, and synaptic transmission. In the present review, we first provide a comprehensive picture of the role of HCN channels in PD by summarizing their role in the regulation of neuronal activity in PD-related brain regions. Dysfunction of I h may participate in 1-methyl-4-phenylpyridinium (MPP+)-induced toxicity and represent a pathogenic mechanism in PD. Given current reports of the critical role of HCN channels in neuroinflammation and depression, we also discussed the putative contribution of HCN channels in inflammatory processes and non-motor symptoms in PD. In the second section, we summarize how HCN channels regulate the formation of β-amyloid peptide in AD and the role of these channels in learning and memory. Finally, we briefly discuss the effects of HCN channels in ALS and SMA based on existing discoveries.

Genetic evolutionary analysis of soybean mosaic virus populations from three geographic locations in China based on the P1 and CP genes

Soybean mosaic virus (SMV) is one of the major pathogens causing serious soybean losses. Little is known about the genetic structure and evolutionary biology of the SMV population in southwestern China. In this study, 29 SMV isolates were obtained from Sichuan Province, and the genomic regions encoding the first protein (P1) and coat protein (CP) were sequenced. Combined with SMV isolates from the southeastern and northeastern regions of China, the genetic and molecular evolution of SMV was studied. Recombination analysis revealed that intraspecific and interspecific recombination had occurred in the SMV population. A phylogenetic tree based on the P1 gene reflected the geographic origin of the non-interspecific recombinant SMV (SMV-NI), while a tree based on the CP gene did not. Though frequent gene flow of the SMV-NI populations was found between the southeastern and northeastern populations, the southwestern population was relatively independent. Genetic differentiation was significant between the SMV interspecific recombinant (SMV-RI) and the non-interspecific recombinant (SMV-NI) populations. It was interesting to note that there was an almost identical recombination breakpoint in SMV-RI and Watermelon mosaic virus (WMV). Population dynamics showed that SMV-RI might be in an expanding state, while the SMV-NI population is relatively stable.

Prevalence and Risk Factors for Frailty among Community-Dwelling Older People in China: A Systematic Review and Meta-Analysis

OBJECTIVE

To systematically assess the prevalence of frailty, including prefrailty, stratified prevalence according to frailty criteria, gender, age, and region, and the risk factors for frailty in China.

DESIGN

We conducted a systematic literature review and meta-analysis using articles available in 8 databases including PubMed, Cochrane Library, Web of Science, CINAHL Plus, China Knowledge Resource Integrated Database (CNKI), Wanfang Database, Chinese Biomedical Database (CBM), and Weipu Database (VIP).

SETTING

Cross-sectional and cohort data from Chinese community.

PARTICIPANTS

Community-dwelling adults aged 65 and older.

MEASUREMENTS

Two authors independently extracted data based upon predefined criteria. Where data were available we conducted a meta-analysis of frailty parameters using a random-effects model.

RESULTS

We screened 915 different articles, and 14 studies (81258 participants) were ultimately included in this analysis. The prevalence of frailty and prefrailty in individual studies varied from 5.9% to 17.4% and from 26.8% to 62.8%, respectively. The pooled prevalence of frailty and prefrailty were 10% (95% CI: 8% to 12%, I2 = 97.4%, P = 0.000) and 43% (95% CI: 37% to 50%, I2 = 98.0%, P = 0.000), respectively. The pooled frailty prevalence was 8% for the Fried frailty phenotype, 12% for the frail index, and 15% for the FRAIL scale. Age-stratified meta-analyses showed the pooled prevalence of frailty to be 6%, 15%, and 25% for those aged 65-74, 75-84, and ≥85 years old, respectively. The pooled prevalence of frailty was 8% for males and 11% for females. The pooled prevalence of frailty in Mainland China, Taiwan, and Hong Kong was 12%, 8%, and 14%, respectively. The pooled frailty prevalence was 10% in urban areas and 7% in rural areas. After controlling for confounding variables, increasing age (OR = 1.28, 95% CI: 1.2 to 1.36, I2 = 98.0%, P = 0.000), being female (OR = 1.29, 95% CI: 1.16 to 1.43, I2 =92.7%, P=0.000), activities of daily living (ADL) disability (OR = 1.72, 95% CI: 1.57 to 1.90, I2 = 99.7%, P = 0.000), and having three or more chronic diseases (OR = 1.97, 95% CI: 1.78 to 2.18, I2 = 97.5%, P = 0.000) were associated with frailty.

CONCLUSIONS

These findings of this review indicate an overall pooled prevalence of frailty among Chinese community-dwelling older people of 10%. Increasing age, being female, ADL disability, and having three or more chronic diseases were all risk factors for frailty. Further research will be needed to identify additional frailty risk factors in order to better treat and prevent frailty in the community.