1.The Diversity of Filamentous Morphologies and Magnetic Sensitivity Modulated by Diverse MagR Expression in Bacteria
Ya-Fei CHANG ; Jing ZHANG ; Peng ZHANG ; Xiu-Juan ZHOU ; Meng-Ke WEI ; Tian-Tian CAI ; Pei-Qi HE ; Jun-Feng WANG ; Can XIE
Progress in Biochemistry and Biophysics 2026;53(5):1439-1456
Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe2+), whereas clMagR favors ferric iron (Fe3+) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe2+-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe2+/Fe3+ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.
2.The Diversity of Filamentous Morphologies and Magnetic Sensitivity Modulated by Diverse MagR Expression in Bacteria
Ya-Fei CHANG ; Jing ZHANG ; Peng ZHANG ; Xiu-Juan ZHOU ; Meng-Ke WEI ; Tian-Tian CAI ; Pei-Qi HE ; Jun-Feng WANG ; Can XIE
Progress in Biochemistry and Biophysics 2026;53(5):1439-1456
Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe2+), whereas clMagR favors ferric iron (Fe3+) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe2+-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe2+/Fe3+ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.
3.Rapid health technology assessment of the efficacy,safety and cost-effectiveness of vericiguat in the treatment of heart failure
Yijun KE ; Wei WANG ; Can HUANG ; Yong JIN ; Lamei QI
China Pharmacy 2024;35(15):1818-1824
OBJECTIVE To evaluate the efficacy, safety and cost-effectiveness of vericiguat in the treatment of heart failure (HF) by rapid health technology evaluation method, and provide reference for the selection and decision-making of clinical treatment plans. METHODS Chinese and foreign databases such as CNKI, PubMed and related health technology evaluation websites were searched by computer. Relevant researchers independently screened literature, extracted data, and comprehensively analyzed the results of the included literature based on literature quality evaluation. RESULTS A total of 17 pieces of literature were included, involving 12 systematic reviews/meta-analyses and 5 pharmacoeconomic studies. The effectiveness analysis showed: for HF patients, compared with placebo, vericiguat (10 mg/d) significantly improved the EuroQol five dimensions questionnaire (EQ-5D) index and decreased the rate of hospitalization due to HF (P<0.05). For heart failure with reduced ejection fraction (HFrEF) patients, vericiguat reduced the incidence of hospitalization due to HF compared with sodium-glucose cotransporter 2 inhibitor (SGLT2i)(P<0.05); compared with angiotensin-converting enzyme inhibitor, vericiguat significantly reduced the occurrence risk of composite endpoints of cardiovascular death or hospitalization due to HF(P<0.05). For HFrEF patients with chronic kidney disease, vericiguat had a tendency to reduce the occurrence risk of composite endpoints of cardiovascular death or hospitalization due to HF compared with neurohormone inhibitors. Safety analysis showed: vericiguat did not increase drug-related adverse reactions compared to placebo (P>0.05). Economic analysis showed: domestic studies indicated that vericiguat had a higher incremental cost-effectiveness ratio. CONCLUSIONS Vericiguat has good safety and efficacy in the treatment of HF but does not possess an economic advantage in the Chinese population.
4.Standardized operational protocol for the China Human Brain Bank Consortium(2nd edition)
Xue WANG ; Zhen CHEN ; Juan-Li WU ; Nai-Li WANG ; Di ZHANG ; Juan DU ; Liang YU ; Wan-Ru DUAN ; Peng-Hao LIU ; Han-Lin ZHANG ; Can HUANG ; Yue-Shan PIAO ; Ke-Qing ZHU ; Ai-Min BAO ; Jing ZHANG ; Yi SHEN ; Chao MA ; Wen-Ying QIU ; Xiao-Jing QIAN
Acta Anatomica Sinica 2024;55(6):734-745
Human brain banks use a standardized protocol to collect,process and store post-mortem human brains and related tissues,along with relevant clinical information,and to provide the tissue samples and data as a resource to foster neuroscience research according to a standardized operating protocols(SOP).Human brain bank serves as the foundation for neuroscience research and the diagnosis of neurological disorders,highlighting the crucial rule of ensuring the consistency of standardized quality for brain tissue samples.The first version of SOP in 2017 was published by the China Human Brain Bank Consortium.As members increases from different regions in China,a revised SOP was drafted by experts from the China Human Brain Bank Consortium to meet the growing demands for neuroscience research.The revised SOP places a strong emphasis on ethical standards,incorporates neuropathological evaluation of brain regions,and provides clarity on spinal cord sampling and pathological assessment.Notable enhancements in this updated version of the SOP include reinforced ethical guidelines,inclusion of matching controls in recruitment,and expansion of brain regions to be sampled for neuropathological evaluation.
5.Berberine regulates glucose and lipid metabolism via clock-controlled genes to ameliorate insulin resistance of hepatocytes.
Li-Ke YAN ; Can CUI ; Ying WANG ; Shui-Lan ZHU ; Zhong-Hua XU ; Han-Yue XIAO ; Wei-Hua LIU ; Jun TU
China Journal of Chinese Materia Medica 2024;49(23):6368-6377
This study aims to investigate the mechanism of berberine in regulating the metabolism network via clock-controlled genes represented by brain and muscle arnt-like 1(BMAL1) to ameliorate insulin resistance(IR) of hepatocytes in vitro. The HepG2 cell model of dexamethasone-induced IR(IR-HepG2) was established and treated with 5, 10, and 20 μmol·L~(-1) berberine, respectively, for 24 h. The glucose oxidase method and cell counting kit-8(CCK-8) assay were employed to measure extracellular glucose concentration and cell viability, respectively. Periodic acid-Schiff(PAS) staining and lipid fluorescence method were used to detect glycogen and lipids. The immunofluorescence(IF) assay was employed to detect the nuclear localization of BMAL1 and circadian locomotor output cycles kaput(CLOCK) in IR-HepG2 cells. Western blot was employed to determine the protein levels of BMAL1, CLOCK, period circadian clock 2(PER2), cryptochrome circadian regulator 1(CRY1), Rev-Erbα, carbohydrate response element-binding protein(ChREBP), peroxisome proliferator-activated receptors alpha and gamma(PPARα/γ), sterol regulatory element-binding protein 1C(SREBP-1C), mammalian target of rapamycin(mTOR), protein kinase B(Akt), glycogen synthase kinase-3β(GSK3β), acetyl coenzyme A carboxylase 1(ACC1), fatty acid synthase(FASN), carnitine palmitoyltransferase 1α(CPT1α), nicotinamide phosphoribosyltransferase(NAMPT), silent information regulator 1(SIRT1), adiponectin(ADPN), insulin receptor substrate 2(IRS2), and phosphatidylinositol 3-kinase regulatory subunit p85(PI3Kp85). In addition, the levels of phosphorylated adenosine monophosphate-activated protein kinase alpha(AMPKα), Akt, GSK3β, BMAL1, and mTOR were determined. Furthermore, 20 μmol·L~(-1) CLK8 was added to measure the glucose consumption as well as the protein levels of ChREBP, PPARα, and mTOR in IR-HepG2 cells. The results showed that berberine increased the glucose consumption, lowered the lipid levels, increased the expression and nuclear localization of BMAL1 and CLOCK, and up-regulated the level of BMAL1 in IR-HepG2 cells. Furthermore, berberine up-regulated the levels of ADPN, IRS2, PI3Kp85, p-Akt(Ser473)/Akt, p-mTOR(Ser2448)/mTOR, PPARα, and CPT1α, and down-regulated the levels of p-GSK3β(Ser9)/GSK3β, ChREBP, SREBP-1C, ACC1, and FASN. The addition of CLK8 reduced glucose consumption in IR-HepG2 cells, up-regulated the ChREBP level, and down-regulated PPARα and mTOR levels by inhibiting the BMAL1 and CLOCK interaction. In summary, berberine regulated glucose and lipid metabolism via clock-controlled genes with BMAL1 at the core to ameliorate IR of hepatocytes.
Humans
;
Hepatocytes/drug effects*
;
Lipid Metabolism/drug effects*
;
Glucose/metabolism*
;
Berberine/pharmacology*
;
Insulin Resistance
;
Hep G2 Cells
;
CLOCK Proteins/genetics*
;
ARNTL Transcription Factors/genetics*
6.A descriptive analysis of hyperlipidemia in adult twins in China.
Ke MIAO ; Wei Hua CAO ; Jun LYU ; Can Qing YU ; Sheng Feng WANG ; Tao HUANG ; Dian Jian Yi SUN ; Chun Xiao LIAO ; Yuan Jie PANG ; Zeng Chang PANG ; Min YU ; Hua WANG ; Xian Ping WU ; Zhong DONG ; Fan WU ; Guo Hong JIANG ; Xiao Jie WANG ; Yu LIU ; Jian DENG ; Lin LU ; Wen Jing GAO ; Li Ming LI
Chinese Journal of Epidemiology 2023;44(4):544-551
Objective: To describe the distribution characteristics of hyperlipidemia in adult twins in the Chinese National Twin Registry (CNTR) and explore the effect of genetic and environmental factors on hyperlipidemia. Methods: Twins recruited from the CNTR in 11 project areas across China were included in the study. A total of 69 130 (34 565 pairs) of adult twins with complete information on hyperlipidemia were selected for analysis. The random effect model was used to characterize the population and regional distribution of hyperlipidemia among twins. The concordance rates of hyperlipidemia were calculated in monozygotic twins (MZ) and dizygotic twins (DZ), respectively, to estimate the heritability. Results: The age of all participants was (34.2±12.4) years. This study's prevalence of hyperlipidemia was 1.3% (895/69 130). Twin pairs who were men, older, living in urban areas, married,had junior college degree or above, overweight, obese, insufficient physical activity, current smokers, ex-smokers, current drinkers, and ex-drinkers had a higher prevalence of hyperlipidemia (P<0.05). In within-pair analysis, the concordance rate of hyperlipidemia was 29.1% (118/405) in MZ and 18.1% (57/315) in DZ, and the difference was statistically significant (P<0.05). Stratified by gender, age, and region, the concordance rate of hyperlipidemia in MZ was still higher than that in DZ. Further, in within-same-sex twin pair analyses, the heritability of hyperlipidemia was 13.04% (95%CI: 2.61%-23.47%) in the northern group and 18.59% (95%CI: 4.43%-32.74%) in the female group, respectively. Conclusions: Adult twins were included in this study and were found to have a lower prevalence of hyperlipidemia than in the general population study, with population and regional differences. Genetic factors influence hyperlipidemia, but the genetic effect may vary with gender and area.
Adult
;
Female
;
Humans
;
Male
;
Middle Aged
;
Young Adult
;
China/epidemiology*
;
Diseases in Twins/genetics*
;
Hyperlipidemias/genetics*
;
Metabolic Diseases
;
Twins, Dizygotic
;
Twins, Monozygotic/genetics*
7.Prospective association between physical activity and mortality in patients with chronic kidney disease.
Ke Xiang SHI ; Xue WANG ; Can Qing YU ; Jun LYU ; Yu GUO ; Dian Jian Yi SUN ; Pei PEI ; Qing Mei XIA ; Jun Shi CHEN ; Zheng Ming CHEN ; Li Ming LI
Chinese Journal of Epidemiology 2023;44(5):720-726
Objective: To investigate the prospective association of physical activity with all-cause, cardiovascular disease (CVD), and chronic kidney disease (CKD) mortality in CKD patients in China. Methods: Cox proportional hazard models were used to evaluate the association of total, domain-specific, and intensity-specific physical activity with the risk of all-cause, CVD, and CKD mortality based on data from the baseline survey of China Kadoorie Biobank. Results: During a median follow-up of 11.99 (11.13, 13.03) years, there were 698 deaths in 6 676 CKD patients. Compared with the bottom tertile of total physical activity, participants in the top tertile had a lower risk of all-cause, CVD, and CKD mortality, with hazard ratios (HRs) (95%CIs) of 0.61 (0.47-0.80), 0.40 (0.25-0.65), and 0.25 (0.07-0.85), respectively. Occupational, commuting, and household physical activity were negatively associated with the risk of all-cause and CVD mortality to varying degrees. Participants in the top tertile of occupational physical activity had a lower risk of all-cause (HR=0.56, 95%CI: 0.38-0.82) and CVD (HR=0.39, 95%CI: 0.20-0.74) mortality, those in the top tertile of commuting physical activity had a lower risk of CVD mortality (HR=0.43, 95%CI: 0.22-0.84), and those in the top tertile of household physical activity had a lower risk of all-cause (HR=0.61, 95%CI: 0.45-0.82), CVD (HR=0.44, 95%CI: 0.26-0.76) and CKD (HR=0.03, 95%CI: 0.01-0.17) mortality, compared with the bottom tertile of corresponding physical activity. No association of leisure-time physical activity with mortality was observed. Both low and moderate-vigorous intensity physical activity were negatively associated with the risk of all-cause, CVD and CKD mortality. The corresponding HRs (95%CIs) were 0.64 (0.50-0.82), 0.42 (0.26-0.66) and 0.29 (0.10-0.83) in the top tertile of low intensity physical activity, and the corresponding HRs (95%CIs) were 0.63 (0.48-0.82), 0.39 (0.24-0.64) and 0.23 (0.07-0.73) in the top tertile of moderate-vigorous intensity physical activity. Conclusion: Physical activity can reduce the risk of all-cause, CVD, and CKD mortality in CKD patients.
Humans
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Exercise
;
Motor Activity
;
Cardiovascular Diseases
;
China
;
Renal Insufficiency, Chronic
8.Chinese expert consensus on clinical treatment of adult patients with severe traumatic brain injury complicated by corona virus disease 2019 (version 2023)
Zeli ZHANG ; Shoujia SUN ; Yijun BAO ; Li BIE ; Yunxing CAO ; Yangong CHAO ; Juxiang CHEN ; Wenhua FANG ; Guang FENG ; Lei FENG ; Junfeng FENG ; Liang GAO ; Bingsha HAN ; Ping HAN ; Chenggong HU ; Jin HU ; Rong HU ; Wei HE ; Lijun HOU ; Xianjian HUANG ; Jiyao JIANG ; Rongcai JIANG ; Lihong LI ; Xiaopeng LI ; Jinfang LIU ; Jie LIU ; Shengqing LYU ; Binghui QIU ; Xizhou SUN ; Xiaochuan SUN ; Hengli TIAN ; Ye TIAN ; Ke WANG ; Ning WANG ; Xinjun WANG ; Donghai WANG ; Yuhai WANG ; Jianjun WANG ; Xingong WANG ; Junji WEI ; Feng XU ; Min XU ; Can YAN ; Wei YAN ; Xiaofeng YANG ; Chaohua YANG ; Rui ZHANG ; Yongming ZHANG ; Di ZHAO ; Jianxin ZHU ; Guoyi GAO ; Qibing HUANG
Chinese Journal of Trauma 2023;39(3):193-203
The condition of patients with severe traumatic brain injury (sTBI) complicated by corona virus 2019 disease (COVID-19) is complex. sTBI can significantly increase the probability of COVID-19 developing into severe or critical stage, while COVID-19 can also increase the surgical risk of sTBI and the severity of postoperative lung lesions. There are many contradictions in the treatment process, which brings difficulties to the clinical treatment of such patients. Up to now, there are few clinical studies and therapeutic norms relevant to sTBI complicated by COVID-19. In order to standardize the clinical treatment of such patients, Critical Care Medicine Branch of China International Exchange and Promotive Association for Medical and Healthcare and Editorial Board of Chinese Journal of Trauma organized relevant experts to formulate the Chinese expert consensus on clinical treatment of adult patients with severe traumatic brain injury complicated by corona virus infection 2019 ( version 2023) based on the joint prevention and control mechanism scheme of the State Council and domestic and foreign literatures on sTBI and COVID-19 in the past 3 years of the international epidemic. Fifteen recommendations focused on emergency treatment, emergency surgery and comprehensive management were put forward to provide a guidance for the diagnosis and treatment of sTBI complicated by COVID-19.
9.Prevalence of chronic kidney disease and its association with lifestyle factors in adults from 10 regions of China.
Xue WANG ; Ke Xiang SHI ; Can Qing YU ; Jun LYU ; Yu GUO ; Pei PEI ; Qing Mei XIA ; Huai Dong DU ; Jun Shi CHEN ; Zheng Ming CHEN ; Li Ming LI
Chinese Journal of Epidemiology 2023;44(3):386-392
Objective: To investigate the distribution of chronic kidney disease (CKD) in participants from the China Kadoorie Biobank (CKB) study and evaluate the association between lifestyle risk factors and CKD. Methods: Based on the baseline survey data and follow-up data (as of December 31, 2018) of the CKB study, the differences in CKD cases' area and population distributions were described. Cox proportional hazards regression model was used to estimate the association between lifestyle risk factors and the risk of CKD. Results: A total of 505 147 participants, 4 920 cases of CKD were recorded in 11.26 year follow up with a incidence rate of 83.43/100 000 person-years. Glomerulonephropathy was the most common type. The incidence of CKD was higher in the urban area, men, and the elderly aged 60 years and above (87.83/100 000 person-years, 86.37/100 000 person-years, and 132.06/100 000 person-years). Current male smokers had an increased risk for CKD compared with non-smokers or occasional smokers (HR=1.18, 95%CI: 1.05-1.31). The non-obese population was used as a control group, both general obesity determined by BMI (HR=1.19, 95%CI: 1.10-1.29) and central obesity determined by waist circumference (HR=1.27, 95%CI: 1.19-1.35) were associated with higher risk for CKD. Conclusion: The risks for CKD varied with area and population in the CKB cohort study, and the risk was influenced by multiple lifestyle factors.
Aged
;
Adult
;
Humans
;
Male
;
Cohort Studies
;
Prevalence
;
Prospective Studies
;
Risk Factors
;
Obesity/epidemiology*
;
Renal Insufficiency, Chronic/epidemiology*
;
China/epidemiology*
;
Life Style
;
Body Mass Index
10.Mechanism of Gegen Qinlian Decoction in improving glucose metabolism in vitro and in vivo by alleviating hepatic endoplasmic reticulum stress.
Yue JIANG ; Li-Ke YAN ; Ying WANG ; Jun-Feng DING ; Zhong-Hua XU ; Can CUI ; Jun TU
China Journal of Chinese Materia Medica 2023;48(20):5565-5575
This study investigated the mechanism of Gegen Qinlian Decoction(GQD) in improving glucose metabolism in vitro and in vivo by alleviating endoplasmic reticulum stress(ERS). Molecular docking was used to predict the binding affinity between the main effective plasma components of GQD and ERS-related targets. Liver tissue samples were obtained from normal rats, high-fat-induced diabetic rats, rats treated with metformin, and rats treated with GQD. RNA and protein were extracted. qPCR was used to measure the mRNA expression of ERS marker glucose-regulated protein 78(GRP78), and unfolded protein response(UPR) genes inositol requiring enzyme 1(Ire1), activating transcription factor 6(Atf6), Atf4, C/EBP-homologous protein(Chop), and caspase-12. Western blot was used to detect the protein expression of GRP78, IRE1, protein kinase R-like ER kinase(PERK), ATF6, X-box binding protein 1(XBP1), ATF4, CHOP, caspase-12, caspase-9, and caspase-3. The calcium ion content in liver tissues was determined by the colorimetric assay. The ERS-HepG2 cell model was established in vitro by inducing with tunicamycin for 6 hours, and 2.5%, 5%, and 10% GQD-containing serum were administered for 9 hours. The glucose oxidase method was used to measure extracellular glucose levels, flow cytometry to detect cell apoptosis, glycogen staining to measure cellular glycogen content, and immunofluorescence to detect the expression of GRP78. The intracellular calcium ion content was measured by the colorimetric assay. Whereas Western blot was used to detect GRP78 and ERS-induced IRE1, PERK, ATF6, and eukaryotic translation initiation factor 2α(eIF2α) phosphorylation. Additionally, the phosphorylation levels of insulin receptor substrate 1(IRS1), phosphatidylinositol 3-kinase regulatory subunit p85(PI3Kp85), and protein kinase B(Akt), which were involved in the insulin signaling pathway, were also measured. In addition, the phosphorylation levels of c-Jun N-terminal kinases(JNKs), which were involved in both the ERS and insulin signaling pathways, were measured by Western blot. Molecular docking results showed that GRP78, IRE1, PERK, ATF4, and various compounds such as baicalein, berberine, daidzein, jateorhizine, liquiritin, palmatine, puerarin and wogonoside had strong binding affinities, indicating that GQD might interfere with ERS-induced UPR. In vivo results showed that GQD down-regulated the mRNA transcription of Ire1, Atf6, Atf4, Grp78, caspase-12, and Chop in diabetic rats, and down-regulated GRP78, IRE1, PERK, as well as ERS-induced apoptotic factors ATF4 and CHOP, caspase-12, caspase-9, and caspase-3, while up-regulating XBP1 to enhance adaptive UPR. In addition, GQD increased the calcium ion content in liver tissues, which facilitated correct protein folding. In vitro results showed that GQD increased glucose consumption in ERS-induced HepG2 cells without significantly affecting cell viability, increased liver glycogen synthesis, down-regulated ATF6 and p-eIF2α(Ser51), and down-regulated IRE1, PERK, and GRP78, as well as p-IRS1(Ser312) and p-JNKs(Thr183/Tyr185), while up-regulating p-PI3Kp85(Tyr607) and p-Akt(Ser473). These findings suggested that GQD alleviates excessive ERS in the liver, reduces insulin resistance, and improves hepatic glucose metabolism in vivo and in vitro.
Rats
;
Animals
;
Proto-Oncogene Proteins c-akt
;
Endoplasmic Reticulum Chaperone BiP
;
Caspase 3
;
Caspase 9
;
Diabetes Mellitus, Experimental
;
Caspase 12
;
Calcium/pharmacology*
;
Molecular Docking Simulation
;
Endoplasmic Reticulum Stress
;
Protein Serine-Threonine Kinases/genetics*
;
Liver
;
Apoptosis
;
Insulin
;
Glucose
;
Glycogen/pharmacology*
;
RNA, Messenger

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