Diabetes and Parkinson's Disease: Debating the Link Through Ca2+/cAMP Signalling

Network pharmacology combined with molecular docking and experimental verification to elucidate functional mechanism of Fufang Zhenzhu Tiaozhi against type 2 diabetes mellitus

Fufang Zhenzhu Tiaozhi (FTZ) capsules have been prescribed for treating glucose and lipid metabolism disorders such as type 2 diabetes mellitus (T2DM). However, the underlying mechanism remains unknown. In this study, network pharmacology and experimental verification were combined to investigate the mechanisms of FTZ in treating T2DM. A total of 176 active ingredients and 1169 corresponding targets were screened using biological databases. 598 potential targets of T2DM were retrieved from GeneCards, PharmGKB, OMIM, Drugbank, and TTD. The Venn diagram was employed to identify the 194 intersection targets, which were employed to construct the "Herb-Compound-Target" interacting networks. These common targets were also used to prepare a protein-protein interaction (PPI) network to uncover potential targets. The four core targets were docked to their corresponding targets for binding analysis. Additionally, the top-ranked poses of ingredients and the positive compounds from each protein were evaluated for stability using molecular dynamics. Our results suggest that core active ingredients such as kaempferol, luteolin, and baicalein have high binding affinity and stability with AKT1, PTGS2 (also known as COX-2), DPP4, and PAPRG. GO and KEGG analyses indicated that the treatment T2DM by FTZ might be related to different pathway like AMPK and EGFR pathways. The experimental validation results proved that kaempferol, luteolin, and baicalein could significantly inhibit the activity of DPP4 and COX-2, kaempferol and luteolin were also able to activate AKT and AMPK signaling pathway. This study further validated previous findings and enhanced our understanding of the potential effects of FTZ on T2DM.Communicated by Ramaswamy H. Sarma.

Regulatory mechanisms of the green alga Ulva lactuca oligosaccharide via the metabolomics and gut microbiome in diabetic mice

Type 2 diabetes (T2D) has emerged as one of the most acute public health diseases of the present time, which increases with the population ageing. This study aimed to evaluate the hypoglycaemic activity of Ulva lactuca oligosaccharide (ULO) under ageing-related diabetes conditions in an animal model. The results demonstrated that ULO can promote hypoglycaemia and delay senescence as mediated via GLP-1/GLP-1R pathway to mobilize the intercommunication between the brain and gut. In addition, twenty-six different metabolites and eight different bacteria were screened in the brain and the gut, respectively. A network relationship displayed that all-trans-retinoic acid has positive relationships with Bifidobacterium and Streptococcus, suggesting that plays a potential key role in maintaining the hypoglycaemic and anti-ageing activities of ULO. Based on these findings, ULO might be an efficient therapy for restoring blood glucose metabolism and delaying brain senescence in elderly T2D patients.

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U. lactuca oligosaccharide (ULO) acts as a GLP-1/GLP-1R agonist to control circulating glucose.

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ULO significantly reduces the expression of brain aging factor p16^Ink4a.

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All-trans-Retinoic acid and Streptococcus are the key mediators of hypoglycemia.

Computational study on new natural compound agonists of dopamine receptor

Dopamine receptor, a polypeptide chain composed of 7 hydrophobic transmembrane regions, is a new and vital drug target, especially Dopamine receptor 2(D2). Targeting dopamine receptors, Dopamine receptor agonists are a class of drugs similar in function and structure to dopamine and can directly act on dopamine receptors and activate it. Clinically, Dopamine receptor agonist drugs have achieved significant therapeutic effects on prolactinoma and Parkinson's Disease. In the study, we virtually screened a series of potential effective agonists of Dopamine receptor by computer techniques. Firstly, we used the Molecular Docking (LibDock) step to screen out some molecules that can dock well with the protein. Then, analysis of toxicity prediction and ADME (adsorption, distribution, metabolism and excretion) were carried out. More precise molecular docking (CDOCKER) and 3-Dimensional Quantitative Structure-Activity Relationship Modeling Study(3D-QSAR) pharmacophore generation were implemented to research and explore these compounds' binding mechanism with Dopamine receptor. Last but not least, to assess compound's binding stabilities, we carried out a molecular dynamic analysis. As the results show, two compounds (ZINC000008860530 and ZINC000004096987) from the small molecule database (ZINC database) were potential effective agonists of Dopamine receptor. These two compounds can combine with Dopamine receptor with higher affinity and proved to be no toxic. The cell experiment showed that two compounds could inhibit the proliferation and PRL secretion of MMQ cells (pituitary tumor cells). Thus, this study provided valuable information about Dopamine receptor agonist-based drug discovery. So, this study will benefit patients with prolactinoma and Parkinson's disease a lot.

Diabetes and inflammatory diseases: An overview from the perspective of Ca2+/3'-5'-cyclic adenosine monophosphate signaling

A large amount of evidence has supported a clinical link between diabetes and inflammatory diseases, e.g., cancer, dementia, and hypertension. In addition, it is also suggested that dysregulations related to Ca²⁺ signaling could link these diseases, in addition to 3'-5'-cyclic adenosine monophosphate (cAMP) signaling pathways. Thus, revealing this interplay between diabetes and inflammatory diseases may provide novel insights into the pathogenesis of these diseases. Publications involving signaling pathways related to Ca²⁺ and cAMP, inflammation, diabetes, dementia, cancer, and hypertension (alone or combined) were collected by searching PubMed and EMBASE. Both signaling pathways, Ca²⁺ and cAMP signaling, control the release of neurotransmitters and hormones, in addition to neurodegeneration, and tumor growth. Furthermore, there is a clear relationship between Ca²⁺ signaling, e.g., increased Ca²⁺ signals, and inflammatory responses. cAMP also regulates pro- and anti-inflammatory responses. Due to the experience of our group in this field, this article discusses the role of Ca²⁺ and cAMP signaling in the correlation between diabetes and inflammatory diseases, including its pharmacological implications. As a novelty, this article also includes: (1) A timeline of the major events in Ca²⁺/cAMP signaling; and (2) As coronavirus disease 2019 (COVID-19) is an emerging and rapidly evolving situation, this article also discusses recent reports on the role of Ca²⁺ channel blockers for preventing Ca²⁺ signaling disruption due to COVID-19, including the correlation between COVID-19 and diabetes.

Heart Matters: Cardiac Dysfunction and Other Autonomic Changes in Parkinson's Disease

It has been more than 200 years since James Parkinson made the first descriptions of the disease that bears his name. Since then, knowledge about Parkinson's disease has been improved, and its pathophysiology, diagnosis, and treatments are well described in the scientific and medical literature. However, there is no way to prevent the disease from its progressive nature yet and only its symptoms can be minimized. It is known that the process of neurodegeneration begins before the onset of motor signs and symptoms of the disease, when diagnosis is usually made. Therefore, recognizing manifested non-motor symptoms can make an early diagnosis possible and lead to a better understanding of the disease. Autonomic dysfunctions are important non-motor manifestations of Parkinson's disease and affect the majority of patients. Importantly, heart failure is the third leading cause of death in people suffering from Parkinson's disease. Several evidences have shown the correlation between Parkinson's disease and the preexistence of cardiovascular diseases. Therefore, cardiovascular monitoring and identification of its dysfunctions can have a prodromal role for Parkinson's disease. This review presents studies of the literature that can lead to a better understanding of Parkinson's disease with special attention to its relation to heart and cardiovascular parameters.

An edge-based statistical analysis of long non-coding RNA expression profiles reveals a negative association between Parkinson's disease and colon cancer

BACKGROUND

Colon cancer (CC) is one of the most common malignant tumors, while Parkinson's disease (PD) is the second most common neurodegenerative disorder. Recent accumulating evidence indicates that these two diseases are associated with each other. Also, from the perspective of long non-coding RNAs, some well-known genes such as H19 and PVT1 can link these two diseases together. Several studies have shown that patients with PD had a decreased risk of developing CC compared with patients without PD. However, controversies surround the relationship between PD and CC, and to date, no concordant conclusion has been drawn.

METHODS

In this study, we aimed to assess the association between these two diseases based on lncRNA-to-lncRNA interactions. Motivated by the weighted gene co-expression network analysis method, a customized procedure was proposed and used to identify differentially correlated edges (DCEs) in the respective interaction networks for PD and CC and explore how these two diseases are linked.

RESULTS

Of the two sets of DCEs for PD and CC, 16 pairs overlapped. Among them, 15 edges had opposite signs, with positive signs for CC indicating a gain of connectivity, whereas negative signs for PD indicating a loss of connectivity.

CONCLUSIONS

By using the lncRNA expression profiles, and a customized procedure, an answer to the question about how PD and CC are associated is provided.

Combatting Nitrosative Stress and Inflammation with Novel Substituted Triazinoindole Inhibitors of Aldose Reductase in PC12 Cells Exposed to 6-Hydroxydopamine Plus High Glucose

Cellular redox dysregulation produced by aldose reductase (AR) in the presence of high blood sugar is a mechanism involved in neurodegeneration commonly observed in diabetes mellitus (DM) and Parkinson's disease (PD); therefore, AR is a key target for treatment of both diseases. The substituted triazinoindole derivatives 2-(3-thioxo-2H-[1,2,4]triazino[5,6-b]indol-5(3H)-yl) acetic acid (cemtirestat or CMTI) and 2-(3-oxo-2H-[1,2,4]triazino[5,6-b]indol-5(3H)-yl) acetic acid (COTI) are well-known AR inhibitors (ARIs). The neuroprotective properties of CMTI, COTI, the clinically used epalrestat (EPA), and the pyridoindole antioxidants stobadine and SMe1EC2 were all tested in the neurotoxic models produced by hyperglycemic glucotoxicity (HG, 75 mM D-glucose, 72 h), 6-hydroxydopamine (6-OHDA), and HG+6-OHDA models in PC12 cells. Cell viability decreased in all toxic models, increased by 1-5 μM EPA, and decreased by COTI at ≥ 2.5 μM. In the HG model alone, where compounds were present in the medium for 24 h after a continuous 24-h exposure to HG, cell viability was improved by 100 nM-5 μM EPA, 1-10 μM ARIs, and the antioxidants studied, but decreased by EPA at ≥ 10 μM. In the 6-OHDA model alone, where cells were treated with compounds for 24 h and further exposed to 100 μM 6-OHDA (8 h), only the antioxidants protected cell viability. In the HG+6-OHDA model, where cells were treated with all compounds (1 nM to 50 μM) for 48 h and exposed to 75 mM glucose for 24 h followed by incubation with 6-OHDA for 8 h, cell viability was protected by 100 nM-10 μM ARIs and 100-500 nM EPA, but not by antioxidants. All ARIs inhibited the HG+6-OHDA-induced increase in iNOS, IL-1β, TNF-α, 3-NT, and total oxidant status at 1-50 μM, while increased SOD, CAT, GPx, and total antioxidant status at 1-10 μM. EPA and CMTI also reduced the HG+6-OHDA-induced increase in the cellular levels of nuclear factor kB (NF-KB). The neuroprotective potential of the novel ARIs and the pyridoindole antioxidants studied constitutes a promising tool for the development of therapeutic strategies against DM-induced and PD-related neurodegeneration.

A link among schizophrenia, diabetes, and asthma: Role of Ca2+/cAMP signaling

Asthma has been associated with an increased risk for developing schizophrenia. In addition, schizophrenia has been associated with an increased risk for developing type 2 diabetes mellitus, resulting in an elevated cardiovascular risk and in a limited life expectancy. It is well discussed that dysregulations related to Ca²⁺ signaling could link these diseases, in addition to cAMP signaling pathways. Thus, revealing this interplay among schizophrenia, diabetes, and asthma may provide novel insights into the pathogenesis of these diseases. Publications involving Ca²⁺ and cAMP signaling pathways, schizophrenia, diabetes, and asthma (alone or combined) were collected by searching PubMed and EMBASE. Both Ca²⁺ and cAMP signaling pathways (Ca²⁺/cAMP signaling) control the release of neurotransmitters and hormones, in addition to airway smooth muscle contractility, then dysregulations of these cellular processes may be involved in these diseases. Taking into consideration, the experience of our group in this field, this narrative review debated the involvement of Ca²⁺/cAMP signaling in this link among schizophrenia, diabetes, and asthma, including its pharmacological implications.

Nanocurcumin improved glucose metabolism in streptozotocin-induced diabetic rats: a comparison study with Gliclazide

In the present study, the biochemical effect of nanocurcumin (nanoCUR) compared with Gliclazide (GLZ) on the diabetic rats was studied. Forty male albino rats (Sprague Dawley) weighted 110 ± 20 g were used. Rats were randomly separated into two groups. Control, received no treatment. Streptozotocin (STZ)-induced diabetic groups take 5 ml/kg of STZ in normal saline daily for 30 days, further divided into diabetic non-treated group, did not receive any treatment: diabetic group treated by nanoCUR, received 15 mg/kg/day of nanoCUR orally for 30 days; diabetic group treated by GLZ, received 2 mg/kg/day of GLZ for 30 days. The mean body weights of all rats were registered and serum samples were collected for determination of fasting blood glucose (FBG), insulin concentration, liver glucokinase (GK), and glycogen synthase (GS) activities. Liver tissues were collected for determination of mRNA expression of insulin (INS), insulin receptor A (IRA), glucokinase (GK), and glucose transporter 2 (GLUT2). The results revealed a significant reduction of body weight in diabetic rats, with no significant differences in nanoCUR and GLZ groups. There was a decline in FBG levels and significant elevation of INS levels, GK, and GS activities in diabetic rats received nanoCUR and GLZ. mRNA expression of INS, IRA, GK, and GLUT2 significantly upregulated in diabetic rats received nanoCUR and GLZ. The amazing observation was a non-significant difference in all measured parameters between nanoCUR and GLZ groups. In conclusion, nanoCUR is able to improve cellular uptake of glucose, the hepatic insulin signaling, and insulin sensitivity in diabetic rats. Its effect was similar to standard hypoglycemic drug (GLZ).