1
|
Xu Q, Wang L, Song Q, Chen S, Du K, Teng X, Zou C. Distinct Hippocampal Expression Profiles of lncRNAs in Obese Type 2 Diabetes Mice Exhibiting Cognitive Impairment. Neuromolecular Med 2024; 26:42. [PMID: 39470862 DOI: 10.1007/s12017-024-08811-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Accepted: 10/18/2024] [Indexed: 11/01/2024]
Abstract
Cognitive dysfunction has been accepted as a possible complication of type 2 diabetes (T2D), but few studies revealed the potential roles of Long non‑coding RNAs (lncRNAs) in cognitive dysfunction in T2D. The current research aims to demonstrate the specific expression patterns of lncRNA-mRNA in the hippocampi of T2D db/db mice exhibiting cognitive impairment. In this study, the results from behavioral tests showed that T2D db/db mice displayed short-term and spatial working memory deficits compared to db/m mice. Furthermore, western blot analysis demonstrated that compared with db/m mice, p-GSK3β (ser9) protein levels were markedly elevated in T2D db/db mice (P < 0.01). In addition, though not statistically significant, the ratio of p-Tau (Ser396) to Tau 46, α-Synuclein expression, and p-GSK3α (ser21) expression were also relatively higher in T2D db/db mice than in db/m mice. The microarray profiling revealed that 75 lncRNAs and 26 mRNAs were dysregulated in T2D db/db mice (> 2.0 fold change, P < 0.05). GO analysis demonstrated that the differentially expressed mRNAs participated in immune response, extracellular membrane-bounded organelle, and extracellular region. KEGG analysis revealed that the differentially expressed mRNAs were mainly involved in one carbon pool by folate, glyoxylate and dicarboxylate metabolism, autophagy, glycine, serine and threonine metabolism, and B cell receptor signaling pathway. A lncRNA‑mRNA coexpression network containing 71 lncRNAs and 26 mRNAs was built to investigate the interaction between lncRNA and mRNA. Collectively, these results revealed the differential hippocampal expression profiles of lncRNAs in T2D mice with cognitive dysfunction, and the findings from this study provide new clues for exploring the potential roles of lncRNAs in the pathogenesis of cognitive dysfunction in T2D.
Collapse
Affiliation(s)
- Qianqian Xu
- Key Laboratory of Longevity and Aging-Related Disease of Chinese Ministry of Education, Center for Translational Medicine and School of Preclinical Medicine, Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Lihui Wang
- Key Laboratory of Longevity and Aging-Related Disease of Chinese Ministry of Education, Center for Translational Medicine and School of Preclinical Medicine, Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Qiong Song
- Key Laboratory of Longevity and Aging-Related Disease of Chinese Ministry of Education, Center for Translational Medicine and School of Preclinical Medicine, Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Shuai Chen
- Key Laboratory of Longevity and Aging-Related Disease of Chinese Ministry of Education, Center for Translational Medicine and School of Preclinical Medicine, Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Kechen Du
- Key Laboratory of Longevity and Aging-Related Disease of Chinese Ministry of Education, Center for Translational Medicine and School of Preclinical Medicine, Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Xiahong Teng
- School of International Education, Guangxi Medical University, Nanning, 530021, Guangxi, China.
| | - Chunlin Zou
- Key Laboratory of Longevity and Aging-Related Disease of Chinese Ministry of Education, Center for Translational Medicine and School of Preclinical Medicine, Guangxi Medical University, Nanning, 530021, Guangxi, China.
- Collaborative Innovation Centre of Regenerative Medicine and Medical BioResource Development and Application Co-Constructed By the Province and Ministry, Guangxi Key Laboratory of Regenerative Medicine, Nanning, Guangxi, China.
- Department of Human Anatomy, Institute of Neuroscience and Guangxi Key Laboratory of Brain Science, School of Basic Medical Sciences, Guangxi Medical University, Nanning, Guangxi, China.
| |
Collapse
|
2
|
Bao X, He Y, Huang L, Li H, Li Q, Huang Y. Sinomenine exerts a neuroprotective effect on PD mouse model through inhibiting PI3K/AKT/mTOR pathway to enhance autophagy. Int J Neurosci 2024; 134:301-309. [PMID: 35815397 DOI: 10.1080/00207454.2022.2100780] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 06/21/2022] [Accepted: 06/30/2022] [Indexed: 10/17/2022]
Abstract
BACKGROUND Parkinson's disease (PD), as a chronic and progressive neurodegenerative disease, is associated with autophagy. This study focused on the regulation of sinomenine (SN) on autophagy in PD and its related mechanism. METHODS The PD mouse model was constructed by MPTP inducement, and the mouse motor function after modeling and SN treatment was examined by rotarod, grip strength, and foot printing tests. Tyrosine hydroxylase (TH)/LC3B-positive neurons in the substantia nigra pars compacta of mouse brains were detected by immunofluorescence. The expressions of proteins related to autophagy (Beclin1, p62, LC3-I and LC3-II) and phosphorylated phosphoinositide 3-kinase (PI3K)/AKT/mechanistic target of rapamycin kinase (mTOR) signaling pathway were measured by western blot. Rescue experiments were performed to determine the effects of MHY1485 (mTOR activator) on SN-treated PD mice. RESULTS SN potentiated the motor ability in PD mice, promoted the survival of dopaminergic neurons, increased the protein expression level of Beclin1, LC3-II/LC3-I ratio and LC3B-positive neurons, lowered the protein expression level of p62 and inactivated PI3K/AKT/mTOR pathway in the substantia nigra tissue of mouse brains. Moreover, MHY1485 reversed the above effects of SN on PD mice via reactivating PI3K/AKT/mTOR pathway. CONCLUSION SN augments the autophagy of dopaminergic neurons via inhibiting the PI3K/AKT/mTOR pathway and exerts a neuroprotective effect on PD mice.
Collapse
Affiliation(s)
- Xi Bao
- Department of Geriatrics, Hangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Yingchun He
- Department of Geriatrics, Hangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Lin Huang
- Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Haichang Li
- Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Qiang Li
- Department of Geriatrics, Hangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Yun Huang
- Department of Chinese Medicine Gynecology, Hangzhou TCM Hospital, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| |
Collapse
|
3
|
Delle C, Wang X, Giannetto M, Newbold E, Peng W, Gomolka RS, Ladrón-de-Guevara A, Cankar N, Schiøler Nielsen E, Kjaerby C, Weikop P, Mori Y, Nedergaard M. Transient but not chronic hyperglycemia accelerates ocular glymphatic transport. Fluids Barriers CNS 2024; 21:26. [PMID: 38475818 DOI: 10.1186/s12987-024-00524-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Accepted: 02/20/2024] [Indexed: 03/14/2024] Open
Abstract
Glymphatic transport is vital for the physiological homeostasis of the retina and optic nerve. Pathological alterations of ocular glymphatic fluid transport and enlarged perivascular spaces have been described in glaucomatous mice. It remains to be established how diabetic retinopathy, which impairs vision in about 50% of diabetes patients, impacts ocular glymphatic fluid transport. Here, we examined ocular glymphatic transport in chronic hyperglycemic diabetic mice as well as in healthy mice experiencing a daily transient increase in blood glucose. Mice suffering from severe diabetes for two and four months, induced by streptozotocin, exhibited no alterations in ocular glymphatic fluid transport in the optic nerve compared to age-matched, non-diabetic controls. In contrast, transient increases in blood glucose induced by repeated daily glucose injections in healthy, awake, non-diabetic mice accelerated antero- and retrograde ocular glymphatic transport. Structural analysis showed enlarged perivascular spaces in the optic nerves of glucose-treated mice, which were absent in diabetic mice. Thus, transient repeated hyperglycemic events, but not constant hyperglycemia, ultimately enlarge perivascular spaces in the murine optic nerve. These findings indicate that fluid transport in the mouse eye is vulnerable to fluctuating glycemic levels rather than constant hyperglycemia, suggesting that poor glycemic control drives glymphatic malfunction and perivascular enlargement in the optic nerve.
Collapse
Affiliation(s)
- Christine Delle
- Center for Translational Neuromedicine, Faculty of Medical and Health Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark
| | - Xiaowei Wang
- Center for Translational Neuromedicine, University of Rochester Medical School, Elmwood Avenue 601, 14642, Rochester, NY, USA
- School of Medicine, University of California, San Francisco, 10 Koret Way, 94117, San Francisco, CA, USA
| | - Michael Giannetto
- Center for Translational Neuromedicine, University of Rochester Medical School, Elmwood Avenue 601, 14642, Rochester, NY, USA
| | - Evan Newbold
- Center for Translational Neuromedicine, University of Rochester Medical School, Elmwood Avenue 601, 14642, Rochester, NY, USA
| | - Weiguo Peng
- Center for Translational Neuromedicine, University of Rochester Medical School, Elmwood Avenue 601, 14642, Rochester, NY, USA
| | - Ryszard Stefan Gomolka
- Center for Translational Neuromedicine, Faculty of Medical and Health Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark
| | - Antonio Ladrón-de-Guevara
- Center for Translational Neuromedicine, University of Rochester Medical School, Elmwood Avenue 601, 14642, Rochester, NY, USA
| | - Neža Cankar
- Center for Translational Neuromedicine, Faculty of Medical and Health Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark
| | - Elise Schiøler Nielsen
- Center for Translational Neuromedicine, Faculty of Medical and Health Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark
| | - Celia Kjaerby
- Center for Translational Neuromedicine, Faculty of Medical and Health Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark
| | - Pia Weikop
- Center for Translational Neuromedicine, Faculty of Medical and Health Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark
| | - Yuki Mori
- Center for Translational Neuromedicine, Faculty of Medical and Health Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark
| | - Maiken Nedergaard
- Center for Translational Neuromedicine, Faculty of Medical and Health Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark.
- Center for Translational Neuromedicine, University of Rochester Medical School, Elmwood Avenue 601, 14642, Rochester, NY, USA.
| |
Collapse
|
4
|
Yao W, Zhang Q, Zhao Y, Xu X, Zhang S, Wang X. Tangzhiqing decoction attenuates cognitive dysfunction of mice with type 2 diabetes by regulating AMPK/mTOR autophagy signaling pathway. JOURNAL OF ETHNOPHARMACOLOGY 2024; 321:117536. [PMID: 38056539 DOI: 10.1016/j.jep.2023.117536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 11/18/2023] [Accepted: 11/28/2023] [Indexed: 12/08/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Tangzhiqing decoction (TZQD) is an effective prescription developed by Jiangsu Province Hospital of Chinese Medicine for the treatment of diabetes mellitus (DM) and its complications, which has a clear cerebral protective effect on mice with diabetic cognitive dysfunction, but its specific mechanism has not been well elucidated. AIMS OF THE STUDY This study aims to verify the protection of TZQD on cognitive function in mice with type 2 diabetes mellitus (T2DM) and explore the possible underlying mechanisms. MATERIALS AND METHODS Six active ingredients in TZQD were detected using high-performance liquid chromatography analysis. In vivo experiments, the protection of TZQD on cognitive function and hippocampal neurons in type 2 diabetes mice was verified to obtain the optimal intervention dose of TZQD. TZQD and 3-methyladenine (3 MA) respectively or jointly intervened in mice with T2DM for 12 weeks, followed by detecting the cognitive difference, hippocampus cornu ammonis 1 (CA1) region injury, and hippocampal neuronal apoptosis in each group. Simultaneously, the investigation of autophagosome formation and organelle impairment in hippocampal neurons, along with the examination of AMPK/mTOR pathway proteins and autophagy-related proteins, was conducted to elucidate the potential mechanisms, through which TZQD modulates autophagy and enhances cognitive function. In vitro experiments, TZQD-containing serum and AMPK inhibitor Compound C (CC) were used to intervene in mouse hippocampal neuron HT22 cells under high glucose environment, further clarifying the regulatory role of TZQD on the AMPK/mTOR pathway and its impact on HT22 cell apoptosis and autophagy. RESULTS In vivo experiment results showed that TZQD had an obvious hypoglycemic effect. Different doses of TZQD could improve cognitive function and hippocampus damage in diabetes mice, with the middle dose of TZQD showing the best effect. TZQD increased the swimming speed of diabetes mice, improved their spatial recognition and memory ability, and reduced hippocampal neuronal apoptosis, Nissl body injury, and p-tau217 protein deposition. In addition, through transmission electron microscopy (TEM), immunofluorescence, and Western blot (WB) detection, TZQD significantly improved the organelle damage of hippocampal neurons in diabetes mice, promoted the formation of autophagy lysosomes, increased the expression of autophagy-related proteins like Beclin 1, LC3II/LC3I, LAMP1, and LAMP2, reduced the level of P62 and promoted autophagy flow, which, however, were all significantly weakened by 3 MA. Meanwhile, TZQD regulated the expressions of AMPK/mTOR pathway proteins. In vitro experimental study results showed that TZQD can regulate the expression ratio of p-AMPK/AMPK alpha 1 and p-mTOR/mTOR in HT22 cells under high glucose conditions and improved the morphology and vitality of HT22 cells. By employing techniques such as monodansylcadaverine (MDC) staining, Lysosomal red fluorescent probe staining, and Annexin V-FITC/PI double staining, the investigation revealed that TZQD administration resulted in enhanced autophagosome formation, preservation of a lysosomal acidic milieu, and consequent mitigation of HT22 cell apoptosis under high glucose conditions. CONCLUSIONS TZQD can regulate the AMPK/mTOR pathway to activate autophagy to attenuate hippocampal neuronal apoptosis, thereby protecting cognitive function in diabetic mice.
Collapse
Affiliation(s)
- Wenqiang Yao
- First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, 210046, China; Endocrine Department, Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, 210029, China
| | - Qing Zhang
- First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, 210046, China; Endocrine Department, Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, 210029, China
| | - Yun Zhao
- First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, 210046, China
| | - Xiru Xu
- Geriatric Department, Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, 210029, China
| | - Shu Zhang
- Endocrine Department, Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, 210029, China
| | - Xu Wang
- First Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, 210046, China; Endocrine Department, Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, 210029, China.
| |
Collapse
|
5
|
Zhang W, Yuan Y, Cui X, Chen S, Zhuang X. The level of serum retinol-binding protein is associated with diabetic mild cognitive impairment. Brain Res 2024; 1822:148670. [PMID: 37944571 DOI: 10.1016/j.brainres.2023.148670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 10/20/2023] [Accepted: 11/06/2023] [Indexed: 11/12/2023]
Abstract
BACKGROUND Several studies have shown that retinol-binding protein (RBP) is linked to diabetes and neurodegenerative diseases. However, no studies have elucidated the relationship between RBP and diabetic cognitive disorders. OBJECTIVE To determine whether the change characteristics of serum RBP are associated with alterations in cognitive functioning in type 2 diabetes mellitus (T2DM). METHODS In this study, 252 patients with T2DM and 34 people as healthy controls were included. According to the Montreal Cognitive Assessment (MoCA), the diabetic subjects were divided into the mild cognitive impairment (MCI) group and the Non-MCI group. Demographic characteristics and clinical indicators as well as serum RBP levels were analyzed. RESULTS The serum RBP levels in the MCI group were lower compared with the Non-MCI group (P = 0.02). The level of RBP was higher in the diabetes without MCI group than in the healthy control (P < 0.001). Serum RBP levels were positively correlated with MoCA scores (r = 0.178, P = 0.003). Binary Logistic regression model analysis showed that low RBP [odds ratio (OR) = 0.936], old age (OR = 1.074), high fasting blood glucose (OR = 1.164), and low fasting C-peptide (OR = 0.722) may be independent risk factors for diabetic MCI. The ROC curve of serum RBP for predicting diabetic MCI showed that the area under the curve was 0.630. CONCLUSIONS Our study revealed an association between serum RBP and diabetic MCI. Serum RBP levels in diabetic MCI are lower and correlated with cognitive function.
Collapse
Affiliation(s)
- Wenjie Zhang
- Department of General Practice, The Second Hospital of Shandong University, Jinan 250000, China
| | - Yuqi Yuan
- Department of Clinical Epidemiology and Evidence-based Medicine, The Second Hospital of Shandong University, Jinan 250000, China
| | - Xiaoxia Cui
- The Second Hospital of Shandong University, Jinan 250000, China
| | - Shihong Chen
- Department of Endocrinology, The Second Hospital of Shandong University, Jinan 250000, China.
| | - Xianghua Zhuang
- Department of Endocrinology, The Second Hospital of Shandong University, Jinan 250000, China.
| |
Collapse
|
6
|
Zhao X, Bie LY, Pang DR, Li X, Yang LF, Chen DD, Wang YR, Gao Y. The role of autophagy in the treatment of type II diabetes and its complications: a review. Front Endocrinol (Lausanne) 2023; 14:1228045. [PMID: 37810881 PMCID: PMC10551182 DOI: 10.3389/fendo.2023.1228045] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 08/24/2023] [Indexed: 10/10/2023] Open
Abstract
Type II diabetes mellitus (T2DM) is a chronic metabolic disease characterized by prolonged hyperglycemia and insulin resistance (IR). Its incidence is increasing annually, posing a significant threat to human life and health. Consequently, there is an urgent requirement to discover effective drugs and investigate the pathogenesis of T2DM. Autophagy plays a crucial role in maintaining normal islet structure. However, in a state of high glucose, autophagy is inhibited, resulting in impaired islet function, insulin resistance, and complications. Studies have shown that modulating autophagy through activation or inhibition can have a positive impact on the treatment of T2DM and its complications. However, it is important to note that the specific regulatory mechanisms vary depending on the target organ. This review explores the role of autophagy in the pathogenesis of T2DM, taking into account both genetic and external factors. It also provides a summary of reported chemical drugs and traditional Chinese medicine that target the autophagic pathway for the treatment of T2DM and its complications.
Collapse
Affiliation(s)
- Xuan Zhao
- Institute of Pharmaceutical Research, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Lu-Yao Bie
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Dao-Ran Pang
- Institute of Pharmaceutical Research, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Xiao Li
- Innovative Institute of Chinese Medicine and Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Long-Fei Yang
- Institute of Pharmaceutical Research, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Dan-Dan Chen
- Institute of Pharmaceutical Research, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Yue-Rui Wang
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Yan Gao
- Institute of Pharmaceutical Research, Shandong University of Traditional Chinese Medicine, Jinan, China
| |
Collapse
|
7
|
Chen P, Chen X, Zhang H, Chen J, Lin M, Qian H, Gao F, Chen Y, Gong C, Zheng X, Zheng T. Dexmedetomidine Regulates Autophagy via the AMPK/mTOR Pathway to Improve SH-SY5Y-APP Cell Damage Induced by High Glucose. Neuromolecular Med 2023; 25:415-425. [PMID: 37017880 DOI: 10.1007/s12017-023-08745-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 03/25/2023] [Indexed: 04/06/2023]
Abstract
Neurodegenerative diseases and postoperative cognitive dysfunction involve the accumulation of β-amyloid peptide (Aβ). High glucose can inhibit autophagy, which facilitates intracellular Aβ clearance. The α2-adrenoreceptor agonist dexmedetomidine (DEX) can provide neuroprotection against several neurological diseases; however, the mechanism remains unclear. This study investigated whether DEX regulated autophagy via the AMPK/mTOR pathway to improve high glucose-induced neurotoxicity in SH-SY5Y/APP695 cells. SH-SY5Y/APP695 cells were cultured with high glucose with/without DEX. To examine the role of autophagy, the autophagy activator rapamycin (RAPA) and autophagy inhibitor 3-methyladenine (3-MA) were used. The selective AMPK inhibitor compound C was used to investigate the involvement of the AMPK pathway. Cell viability and apoptosis were examined by CCK-8 and annexin V-FITC/PI flow cytometric assays, respectively. Autophagy was analyzed by monodansylcadaverine staining of autophagic vacuoles. Autophagy- and apoptosis-related protein expression and the phosphorylation levels of AMPK/mTOR pathway molecules were quantified by western blotting. DEX pretreatment significantly suppressed high glucose-induced neurotoxicity in SH-SY5Y/APP695 cells, as evidenced by the enhanced viability, restoration of cellular morphology, and reduction in apoptotic cells. Furthermore, RAPA had a protective effect similar to that of DEX, but 3-MA eliminated the protective effect of DEX by promoting mTOR activation. Moreover, the AMPK/mTOR pathway was involved in DEX-mediated autophagy. Compound C significantly suppressed autophagy and reversed the protective effect of DEX against high glucose in SH-SY5Y/APP695 cells. Our findings demonstrated that DEX protected SH-SY5Y/APP695 cells against high glucose-induced neurotoxicity by upregulating autophagy through the AMPK/mTOR pathway, suggesting a role of DEX in treating POCD in diabetic patients.
Collapse
Affiliation(s)
- Pinzhong Chen
- Department of Anesthesiology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, No.134 Dong Street, Fuzhou, 350001, Fujian, People's Republic of China
| | - Xiaohui Chen
- Department of Anesthesiology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, No.134 Dong Street, Fuzhou, 350001, Fujian, People's Republic of China
| | - Honghong Zhang
- Department of Anesthesiology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, No.134 Dong Street, Fuzhou, 350001, Fujian, People's Republic of China
| | - Jianghu Chen
- Department of Anesthesiology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, No.134 Dong Street, Fuzhou, 350001, Fujian, People's Republic of China
| | - Mingxue Lin
- Department of Anesthesiology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, No.134 Dong Street, Fuzhou, 350001, Fujian, People's Republic of China
| | - Haitao Qian
- Department of Anesthesiology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, No.134 Dong Street, Fuzhou, 350001, Fujian, People's Republic of China
| | - Fei Gao
- Department of Anesthesiology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, No.134 Dong Street, Fuzhou, 350001, Fujian, People's Republic of China
| | - Yisheng Chen
- Center for Experimental Research in Clinical Medicine, Fujian Provincial Hospital, No.134 Dong Street, Fuzhou, 350001, Fujian, People's Republic of China
| | - Cansheng Gong
- Department of Anesthesiology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, No.134 Dong Street, Fuzhou, 350001, Fujian, People's Republic of China
| | - Xiaochun Zheng
- Department of Anesthesiology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, No.134 Dong Street, Fuzhou, 350001, Fujian, People's Republic of China.
- Fujian Emergency Medical Center, Fujian Provincial Key Laboratory of Emergency Medicine, Fujian Provincial Key Laboratory of Critical Medicine, Fujian Provincial Co-constructed Laboratory of "Belt and Road", Fuzhou, China.
| | - Ting Zheng
- Department of Anesthesiology, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital, No.134 Dong Street, Fuzhou, 350001, Fujian, People's Republic of China.
| |
Collapse
|
8
|
Lin L, Basu R, Chatterjee D, Templin AT, Flak JN, Johnson TS. Disease-associated astrocytes and microglia markers are upregulated in mice fed high fat diet. Sci Rep 2023; 13:12919. [PMID: 37558676 PMCID: PMC10412627 DOI: 10.1038/s41598-023-39890-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 08/01/2023] [Indexed: 08/11/2023] Open
Abstract
High-fat diet (HFD) is associated with Alzheimer's disease (AD) and type 2 diabetes risk, which share features such as insulin resistance and amylin deposition. We examined gene expression associated with astrocytes and microglia since dysfunction of these cell types is implicated in AD pathogenesis. We hypothesize gene expression changes in disease-associated astrocytes (DAA), disease-associated microglia and human Alzheimer's microglia exist in diabetic and obese individuals before AD development. By analyzing bulk RNA-sequencing (RNA-seq) data generated from brains of mice fed HFD and humans with AD, 11 overlapping AD-associated differentially expressed genes were identified, including Kcnj2, C4b and Ddr1, which are upregulated in response to both HFD and AD. Analysis of single cell RNA-seq (scRNA-seq) data indicated C4b is astrocyte specific. Spatial transcriptomics (ST) revealed C4b colocalizes with Gfad, a known astrocyte marker, and the colocalization of C4b expressing cells with Gad2 expressing cells, i.e., GABAergic neurons, in mouse brain. There also exists a positive correlation between C4b and Gad2 expression in ST indicating a potential interaction between DAA and GABAergic neurons. These findings provide novel links between the pathogenesis of obesity, diabetes and AD and identify C4b as a potential early marker for AD in obese or diabetic individuals.
Collapse
Affiliation(s)
- Li Lin
- Indiana Biosciences Research Institute, Indianapolis, IN, USA
| | - Rashmita Basu
- Indiana Biosciences Research Institute, Indianapolis, IN, USA
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Debolina Chatterjee
- Department of Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Andrew T Templin
- Indiana Biosciences Research Institute, Indianapolis, IN, USA
- Division of Endocrinology, Department of Medicine, Richard L. Roudebush VA Medical Center, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Jonathan N Flak
- Indiana Biosciences Research Institute, Indianapolis, IN, USA
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Travis S Johnson
- Indiana Biosciences Research Institute, Indianapolis, IN, USA.
- Department of Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, IN, USA.
| |
Collapse
|
9
|
Cheng L, Chen Y, Guo D, Zhong Y, Li W, Lin Y, Miao Y. mTOR-dependent TFEB activation and TFEB overexpression enhance autophagy-lysosome pathway and ameliorate Alzheimer's disease-like pathology in diabetic encephalopathy. Cell Commun Signal 2023; 21:91. [PMID: 37143104 PMCID: PMC10158341 DOI: 10.1186/s12964-023-01097-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 03/07/2023] [Indexed: 05/06/2023] Open
Abstract
BACKGROUND Diabetic encephalopathy (DE) is a complication of type 2 diabetes mellitus (T2DM) that features Alzheimer's disease (AD)-like pathology, which can be degraded by the autophagy-lysosome pathway (ALP). Since transcription factor EB (TFEB) is a master regulator of ALP, TFEB-mediated ALP activation might have a therapeutic effect on DE, but this has yet to be investigated. METHODS We established T2DM mouse models and cultured HT22 cells under high-glucose (HG) conditions to confirm the role of ALP in DE. To further investigate this, both mice and HT22 cells were treated with 3-methyladenine (3-MA). We also analyzed the content of TFEB in the nucleus and cytoplasm to evaluate its role in ALP. To confirm the effect of TFEB activation at the post-translational level in DE, we used rapamycin to inhibit the mechanistic target of rapamycin (mTOR). We transduced both mice and cells with TFEB vector to evaluate the therapeutic effect of TFEB overexpression on DE. Conversely, we conducted TFEB knockdown to verify its role in DE in another direction. RESULTS We found that T2DM mice experienced compromised cognitive function, while HG-cultured HT22 cells exhibited increased cell apoptosis. Additionally, both T2DM mice and HG-cultured HT22 cells showed impaired ALP and heavier AD-like pathology. This pathology worsened after treatment with 3-MA. We also observed decreased TFEB nuclear translocation in both T2DM mice and HG-cultured HT22 cells. However, inhibiting mTOR with rapamycin or overexpressing TFEB increased TFEB nuclear translocation, enhancing the clearance of ALP-targeted AD-like pathology. This contributed to protection against neuronal apoptosis and alleviation of cognitive impairment. Conversely, TFEB knockdown lessened ALP-targeted AD-like pathology clearance and had a negative impact on DE. CONCLUSION Our findings suggest that impaired ALP is responsible for the aggravation of AD-like pathology in T2DM. We propose that mTOR-dependent TFEB activation and TFEB overexpression are promising therapeutic strategies for DE, as they enhance the clearance of ALP-targeted AD-like pathology and alleviate neuronal apoptosis. Our study provides insight into the underlying mechanisms of DE and offers potential avenues for the development of new treatments for this debilitating complication of T2DM. Video abstract.
Collapse
Affiliation(s)
- Lizhen Cheng
- Department of Geriatrics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 600 Yishan Road, Xuhui, Shanghai, 200233, People's Republic of China
| | - Yixin Chen
- Department of Geriatrics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 600 Yishan Road, Xuhui, Shanghai, 200233, People's Republic of China
| | - Donghao Guo
- Department of Geriatrics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 600 Yishan Road, Xuhui, Shanghai, 200233, People's Republic of China
- Division of Cardiology, Department of Medicine and Therapeutics, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Yuan Zhong
- Department of Geriatrics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 600 Yishan Road, Xuhui, Shanghai, 200233, People's Republic of China
| | - Wei Li
- Department of Geriatrics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 600 Yishan Road, Xuhui, Shanghai, 200233, People's Republic of China
| | - Yijia Lin
- Department of Geriatrics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 600 Yishan Road, Xuhui, Shanghai, 200233, People's Republic of China
| | - Ya Miao
- Department of Geriatrics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 600 Yishan Road, Xuhui, Shanghai, 200233, People's Republic of China.
| |
Collapse
|
10
|
Wang LH, Wang YY, Liu L, Gong Q. From Diabetes to Diabetic Complications: Role of Autophagy. Curr Med Sci 2023:10.1007/s11596-023-2727-4. [PMID: 37115396 DOI: 10.1007/s11596-023-2727-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 12/29/2022] [Indexed: 04/29/2023]
Abstract
Diabetes and its complications reduce quality of life and are life-limiting. At present, diabetes treatment consists of hypoglycemic agents to control blood glucose and the use of insulin-sensitizing drugs to overcome insulin resistance. In diabetes, autophagy is impaired and thus there is poor intracellular environment homeostasis. Pancreatic β-cells and insulin target tissues are protected by enhancing autophagy. Autophagy decreases β-cell apoptosis, promotes β-cell proliferation, and alleviates insulin resistance. Autophagy in diabetes is regulated by the mammalian target of rapamycin (mTOR)/adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) pathway and others. Autophagy enhancers can likely be used as a treatment for diabetes and its complications. This review examines the evidence linking autophagy to diabetes.
Collapse
Affiliation(s)
- Lin-Hua Wang
- Clinical Molecular Immunology Center, Yangtze University, Jingzhou, 434023, China
| | - Yang-Yang Wang
- Clinical Molecular Immunology Center, Yangtze University, Jingzhou, 434023, China
| | - Lian Liu
- Department of Pharmacology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, 434023, China.
| | - Quan Gong
- Clinical Molecular Immunology Center, Yangtze University, Jingzhou, 434023, China.
- Department of Immunology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, 434023, China.
| |
Collapse
|
11
|
Zhang W, Chen S, Zhuang X. Research Progress on Lipocalin-2 in Diabetic Encephalopathy. Neuroscience 2023; 515:74-82. [PMID: 36805002 DOI: 10.1016/j.neuroscience.2023.02.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 02/07/2023] [Accepted: 02/12/2023] [Indexed: 02/18/2023]
Abstract
Diabetic encephalopathy is a central nervous complication of diabetes mellitus which is characterized by cognitive impairment and structural and neurochemical abnormalities, which is easily neglected. Lipocalin-2 (LCN2) is a 25 kDa transporter in the lipocalin family that can transport small molecules, including fatty acids, iron, steroids, and lipopolysaccharides in the circulation. Recently, LCN2 has been found to be a significant regulator of insulin resistance and glucose homeostasis. Numerous studies have shown that LCN2 is connected to central nervous system abnormalities, including neuroinflammation and neurodegeneration, while the latest researches have found that LCN2 is closely related to the development of diabetic encephalopathy. Nevertheless, its precise role in the pathogenesis of diabetic encephalopathy remains to be determined. In this paper, we review recent evidence on the role of LCN2 in diabetic encephalopathy from multiple perspectives in order to decipher the impact of LCN2 in both the aetiology and treatment of diabetic encephalopathy.
Collapse
Affiliation(s)
- Wenjie Zhang
- Cheeloo College of Medicine, Shangdong University, Jinan 250000, China
| | - Shihong Chen
- Department of Endocrinology, The Second Hospital of Shandong University, Jinan 250000, China.
| | - Xianghua Zhuang
- Department of Endocrinology, The Second Hospital of Shandong University, Jinan 250000, China.
| |
Collapse
|
12
|
Carvalho C, Correia SC, Seiça R, Moreira PI. WWOX inhibition by Zfra1-31 restores mitochondrial homeostasis and viability of neuronal cells exposed to high glucose. Cell Mol Life Sci 2022; 79:487. [PMID: 35984507 PMCID: PMC11071800 DOI: 10.1007/s00018-022-04508-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 07/26/2022] [Accepted: 07/27/2022] [Indexed: 02/04/2023]
Abstract
Diabetes has been associated with an increased risk of cognitive decline and dementia. However, the mechanisms underlying this association remain unclear and no effective therapeutic interventions exist. Accumulating evidence demonstrates that mitochondrial defects are a key feature of diabetes contributing to neurodegenerative events. It has also been demonstrated that the putative tumor suppressor WW domain-containing oxidoreductase 1 (WWOX) can interact with mitochondria in several pathological conditions. However, its role in diabetes-associated neurodegeneration remains unknown. So, this study aimed to evaluate the role of WWOX activation in high glucose-induced neuronal damage and death. Our experiments were mainly performed in differentiated SH-SY5Y neuroblastoma cells exposed to high glucose and treated (or not) with Zfra1-31, the specific inhibitor of WWOX. Several parameters were analyzed namely cell viability, WWOX activation (tyrosine 33 residue phosphorylation), mitochondrial function, reactive oxygen species (ROS) production, biogenesis, and dynamics, autophagy and oxidative stress/damage. The levels of the neurotoxic proteins amyloid β (Aβ) and phosphorylated Tau (pTau) and of synaptic integrity markers were also evaluated. We observed that high glucose increased the levels of activated WWOX. Interestingly, brain cortical and hippocampal homogenates from young (6-month old) diabetic GK rats showed increased levels of activated WWOX compared to older GK rats (12-month old) suggesting that WWOX plays an early role in the diabetic brain. In neuronal cells, high glucose impaired mitochondrial respiration, dynamics and biogenesis, increased mitochondrial ROS production and decreased mitochondrial membrane potential and ATP production. More, high glucose augmented oxidative stress/damage and the levels of Aβ and pTau proteins and affected autophagy, contributing to the loss of synaptic integrity and cell death. Of note, the activation of WWOX preceded mitochondrial dysfunction and cell death. Importantly, the inhibition of WWOX with Zfra1-31 reversed, totally or partially, the alterations promoted by high glucose. Altogether our observations demonstrate that under high glucose conditions WWOX activation contributes to mitochondrial anomalies and neuronal damage and death, which suggests that WWOX is a potential therapeutic target for early interventions. Our findings also support the efficacy of Zfra1-31 in treating hyperglycemia/diabetes-associated neurodegeneration.
Collapse
Affiliation(s)
- Cristina Carvalho
- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504, Coimbra, Portugal.
- Center for Innovation in Biomedicine and Biotechnology (CIBB), Coimbra, Portugal.
- Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal.
| | - Sónia C Correia
- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504, Coimbra, Portugal
- Center for Innovation in Biomedicine and Biotechnology (CIBB), Coimbra, Portugal
- Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
| | - Raquel Seiça
- Institute of Physiology, Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Paula I Moreira
- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504, Coimbra, Portugal.
- Center for Innovation in Biomedicine and Biotechnology (CIBB), Coimbra, Portugal.
- Institute of Physiology, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
- Laboratory of Physiology, Faculty of Medicine, University of Coimbra, 3000-354, Coimbra, Portugal.
| |
Collapse
|
13
|
Du H, Meng X, Yao Y, Xu J. The mechanism and efficacy of GLP-1 receptor agonists in the treatment of Alzheimer's disease. Front Endocrinol (Lausanne) 2022; 13:1033479. [PMID: 36465634 PMCID: PMC9714676 DOI: 10.3389/fendo.2022.1033479] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 10/27/2022] [Indexed: 11/18/2022] Open
Abstract
Since type 2 diabetes mellitus (T2DM) is a risk factor for Alzheimer's disease (AD) and both have the same pathogenesis (e.g., insulin resistance), drugs used to treat T2DM have been gradually found to reduce the progression of AD in AD models. Of these drugs, glucagon-like peptide 1 receptor (GLP-1R) agonists are more effective and have fewer side effects. GLP-1R agonists have reducing neuroinflammation and oxidative stress, neurotrophic effects, decreasing Aβ deposition and tau hyperphosphorylation in AD models, which may be a potential drug for the treatment of AD. However, this needs to be verified by further clinical trials. This study aims to summarize the current information on the mechanisms and effects of GLP-1R agonists in AD.
Collapse
Affiliation(s)
- Haiyang Du
- Division of Orthopedics, Department of Orthopedics, The Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Xiaoyu Meng
- Division of Endocrinology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Branch of National Clinical Research Center for Metabolic Diseases, Hubei, China
| | - Yu Yao
- Division of Orthopedics, Department of Orthopedics, The Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Jun Xu
- Division of Orthopedics, Department of Orthopedics, The Second Affiliated Hospital of Harbin Medical University, Harbin, China
- *Correspondence: Jun Xu,
| |
Collapse
|
14
|
Li X, He Q, Zhao N, Chen X, Li T, Cheng B. High intensity interval training ameliorates cognitive impairment in T2DM mice possibly by improving PI3K/Akt/mTOR Signaling-regulated autophagy in the hippocampus. Brain Res 2021; 1773:147703. [PMID: 34743961 DOI: 10.1016/j.brainres.2021.147703] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 10/11/2021] [Accepted: 10/22/2021] [Indexed: 10/19/2022]
Abstract
Exercise can improve cognitive impairment in type 2 diabetes mellitus (T2DM). However, the underlying mechanisms are not clear, and the optimal exercise modes for cognitive benefits are controversial. The aim of this study was to investigate the effects of high-intensity interval training (HIIT) and moderate-intensity interval training (MICT) on cognitive function and the PI3K/Akt/mTOR pathway as well as autophagy in T2DM mice. The results showed that 8 weeks of HIIT and MICT intervention could improve the spatial learning and memory ability of T2DM mice, as determined by the Morris water maze (MWM) test. Both HIIT and MICT similarly improved autophagy, as evidenced by increased Beclin1 and LC3 II/I ratios and decreased p62. Meanwhile, HIIT and MICT inhibited excessive activation of the PI3K/Akt/mTOR pathway in the hippocampus. HIIT induced a larger reduction in mTOR activity than MICT. This study suggests that both HIIT and MICT can alleviate cognitive decline induced by T2DM, improve autophagy in the hippocampus, and downregulate the excessive activation of the PI3K/Akt/mTOR signaling pathway, with similar effects.
Collapse
Affiliation(s)
- Xuejiao Li
- School of Physical Education of Shandong University, Jinan, China
| | - Qiang He
- School of Physical Education of Shandong University, Jinan, China
| | - Na Zhao
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai, China
| | - Xianghe Chen
- College of Physical Education, Yangzhou University, Yangzhou, China
| | - Tuojian Li
- School of Physical Education of Shandong University, Jinan, China
| | - Bin Cheng
- School of Physical Education of Shandong University, Jinan, China.
| |
Collapse
|
15
|
Autophagy and Tau Protein. Int J Mol Sci 2021; 22:ijms22147475. [PMID: 34299093 PMCID: PMC8303176 DOI: 10.3390/ijms22147475] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 06/22/2021] [Accepted: 07/01/2021] [Indexed: 12/19/2022] Open
Abstract
Neurofibrillary tangles, which consist of highly phosphorylated tau protein, and senile plaques (SPs) are pathological hallmarks of Alzheimer's disease (AD). In swollen axons, many autophagic vacuoles are observed around SP in the AD brain. This suggests that autophagy function is disturbed in AD. We used a neuronal cellular model of tauopathy (M1C cells), which harbors wild type tau (4R0N), to assess the effects of the lysosomotrophic agent NH4Cl, and autophagy inhibitors chloroquine and 3 methyladenine (3MA). It was found that chloroquine, NH4Cl and 3MA markedly increased tau accumulation. Thus, autophagy lysosomal system disturbances disturbed the degradation mechanisms of tau protein. Other studies also revealed that tau protein, including aggregated tau, is degraded via the autophagy lysosome system. Phosphorylated and C terminal truncated tau were also reported to disturb autophagy function. As a therapeutic strategy, autophagy upregulation was suggested. Thus far, as autophagy modulators, rapamycin, mTOCR1 inhibitor and its analogues, lithium, metformin, clonidine, curcumin, nicotinamide, bexaroten, and torehalose have been proposed. As a therapeutic strategy, autophagic modulation may be the next target of AD therapeutics.
Collapse
|
16
|
Carvalho C, Cardoso S. Diabetes-Alzheimer's Disease Link: Targeting Mitochondrial Dysfunction and Redox Imbalance. Antioxid Redox Signal 2021; 34:631-649. [PMID: 32098477 DOI: 10.1089/ars.2020.8056] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Significance: It is of common sense that the world population is aging and life expectancy is increasing. However, as the population ages, there is also an exponential risk to live into the ages where the brain-related frailties and neurodegenerative diseases develop. Hand in hand with those events, the world is witnessing a major upsurge in diabetes diagnostics. Remarkably, all of this seems to be narrowly related, and clinical and research communities highlight for the upcoming threat that it will represent for the present and future generations. Recent Advances: It is of utmost importance to clarify the influence of diabetes-related metabolic features on brain health and the mechanisms underlying the increased likelihood of developing neurodegenerative diseases, in particular Alzheimer's disease. Thereupon, a wealth of evidence suggests that mitochondria and associated oxidative stress are at the root of the link between diabetes and co-occurring disorders in the brain. Critical Issues: The scientific community has been challenged with constant failures of clinical trials raising major issues in the advance of the therapeutic field to fight chronic diseases epidemics. Thus, a change of paradigms is urgently needed. Future Directions: It has become urgent to identify new and solid candidates able to clinically reproduce the positive outcomes obtained in preclinical studies. On this basis, strategies settled to counteract diabetes-induced neurodegeneration encompassing mitochondrial dysfunction, redox status imbalance, and/or insulin dysregulation seem worth to follow. Hopefully, ongoing innovative research based on reliable experimental tools will soon bring the desired answers allowing pharmaceutical industry to apply such knowledge to human medicine.
Collapse
Affiliation(s)
- Cristina Carvalho
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,CIBB-Center for Innovative Biomedicine and Biotechnology, University of Coimbra, Coimbra, Portugal.,IIIUC-Interdisciplinarie Institute of Investigation, University of Coimbra, Coimbra, Portugal
| | - Susana Cardoso
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,CIBB-Center for Innovative Biomedicine and Biotechnology, University of Coimbra, Coimbra, Portugal.,IIIUC-Interdisciplinarie Institute of Investigation, University of Coimbra, Coimbra, Portugal
| |
Collapse
|