Etiologies underlying subtypes of long-standing type 2 diabetes.

BACKGROUND: Attempts to subtype, type 2 diabetes (T2D) have mostly focused on newly diagnosed European patients. In this study, our aim was to subtype T2D in a non-white Emirati ethnic population with long-standing disease, using unsupervised soft clustering, based on etiological determinants. METHODS: The Auto Cluster model in the IBM SPSS Modeler was used to cluster data from 348 Emirati patients with long-standing T2D. Five predictor variables (fasting blood glucose (FBG), fasting serum insulin (FSI), body mass index (BMI), hemoglobin A1c (HbA1c) and age at diagnosis) were used to determine the appropriate number of clusters and their clinical characteristics. Multinomial logistic regression was used to validate clustering results. RESULTS: Five clusters were identified; the first four matched Ahlqvist et al subgroups: severe insulin-resistant diabetes (SIRD), severe insulin-deficient diabetes (SIDD), mild age-related diabetes (MARD), mild obesity-related diabetes (MOD), and a fifth new subtype of mild early onset diabetes (MEOD). The Modeler algorithm allows for soft assignments, in which a data point can be assigned to multiple clusters with different probabilities. There were 151 patients (43%) with membership in cluster peaks with no overlap. The remaining 197 patients (57%) showed extensive overlap between clusters at the base of distributions. CONCLUSIONS: Despite the complex picture of long-standing T2D with comorbidities and complications, our study demonstrates the feasibility of identifying subtypes and their underlying causes. While clustering provides valuable insights into the architecture of T2D subtypes, its application to individual patient management would remain limited due to overlapping characteristics. Therefore, integrating simplified, personalized metabolic profiles with clustering holds greater promise for guiding clinical decisions than subtyping alone.

Risk and predictors of severity and mortality in patients with type 2 diabetes and COVID-19 in Dubai.

BACKGROUND: Globally, patients with diabetes suffer from increased disease severity and mortality due to coronavirus disease 2019 (COVID-19). Old age, high body mass index (BMI), comorbidities, and complications of diabetes are recognized as major risk factors for infection severity and mortality. AIM: To investigate the risk and predictors of higher severity and mortality among in-hospital patients with COVID-19 and type 2 diabetes (T2D) during the first wave of the pandemic in Dubai (March-September 2020). METHODS: In this cross-sectional nested case-control study, a total of 1083 patients with COVID-19 were recruited. This study included 890 men and 193 women. Of these, 427 had T2D and 656 were non-diabetic. The clinical, radiographic, and laboratory data of the patients with and without T2D were compared. Independent predictors of mortality in COVID-19 non-survivors were identified in patients with and without T2D. RESULTS: T2D patients with COVID-19 were older and had higher BMI than those without T2D. They had higher rates of comorbidities such as hypertension, ischemic heart disease, heart failure, and more life-threatening complications. All laboratory parameters of disease severity were significantly higher than in those without T2D. Therefore, these patients had a longer hospital stay and a significantly higher mortality rate. They died from COVID-19 at a rate three times higher than patients without. Most laboratory and radiographic severity indices in non-survivors were high in patients with and without T2D. In the univariate analysis of the predictors of mortality among all COVID-19 non-survivors, significant associations were identified with old age, increased white blood cell count, lym-phopenia, and elevated serum troponin levels. In multivariate analysis, only lymphopenia was identified as an independent predictor of mortality among T2D non-survivors. CONCLUSION: Patients with COVID-19 and T2D were older with higher BMI, more comorbidities, higher disease severity indices, more severe proinflammatory state with cardiac involvement, and died from COVID-19 at three times the rate of patients without T2D. The identified mortality predictors will help healthcare workers prioritize the management of patients with COVID-19.

aza-Flavanones as potent cross-species microRNA inhibitors that arrest cell cycle.

aza-Flavanones have been identified as a new class of selective microRNA inhibitors. These compounds were found to arrest cell cycle via a novel cross species microRNA-dependent regulatory pathway interpreting an unexpected link between cell cycle arrest and microRNA mediated control in cancer.

Chalcone-imidazolone conjugates induce apoptosis through DNA damage pathway by affecting telomeres.

BACKGROUND: Breast cancer is one of the most prevalent cancers in the world and more than one million women are diagnosed leading to 410,000 deaths every year. In our previous studies new chalcone-imidazolone conjugates were prepared and evaluated for their anticancer activity in a panel of 53 human tumor cell lines and the lead compounds identified were 6 and 8. This prompted us to investigate the mechanism of apoptotic event. RESULTS: Involvement of pro-apoptotic protein (Bax), active caspase-9 and cleavage of retinoblastoma protein was studied. Interestingly, the compounds caused upregulation of p21, check point proteins (Chk1, Chk2) and as well as their phosphorylated forms which are known to regulate the DNA damage pathway. Increased p53BP1 foci by immunolocalisation studies and TRF1 suggested the possible involvement of telomere and associated proteins in the apoptotic event. The telomeric protein such as TRF2 which is an important target for anticancer therapy against human breast cancer was extensively studied along with proteins involved in proper functioning of telomeres. CONCLUSIONS: The apoptotic proteins such as Bax, active caspase-9 and cleaved RB are up-regulated in the compound treated cells revealing the apoptotic nature of the compounds. Down regulation of TRF2 and upregulation of the TRF1 as well as telomerase assay indicated the decrease in telomeric length revealing telomeric dysfunction and thereby controlling the rapid rate of cell proliferation. In summary, chalcone-imidazolone conjugates displayed significant DNA damage activity particularly at telomeres and caused both apoptosis and senescence-like growth arrest which suggested that these compounds have potential activity against breast carcinoma.

Identification of Novel MicroRNAs as Promising Therapeutics for SARS-CoV-2 by Regulating the EGFR-ADAM17 Axis: An In Silico Analysis.

Cancer patients contracting SARS-CoV-2 encounter additional challenges due to inflammatory bursts and lymphopenia, which may aggravate breast cancer prognosis. In this in silico analysis, we identified the potential of miRNAs as new therapeutic targets to treat breast cancer patients infected with COVID-19 via the regulation of ADAM17 and EGFR expression microRNAs.

Identification of Novel MicroRNAs Targeting SARS-CoV-2 through the Regulation of TMPRSS2/PI3K/AKT/PTEN Alignment in Lung Cancer: An in Silico Analysis.

In this study, we investigated the interactions between SARS-CoV-2 and miRNAs associated with lung cancer using bioinformatic approaches. A special focus was placed on TMPRSS2 and lung cancer progression pathways involving AKT/PI3K/PTEN genes.

Ultrasound-Mediated Cancer Therapeutics Delivery using Micelles and Liposomes: A Review.

BACKGROUND: Existing cancer treatment methods have many undesirable side effects that greatly reduce the quality of life of cancer patients. OBJECTIVE: This review will focus on the use of ultrasound-responsive liposomes and polymeric micelles in cancer therapy. METHODS: This review presents a survey of the literature regarding ultrasound-triggered micelles and liposomes using articles recently published in various journals, as well as some new patents in this field. RESULTS: Nanoparticles have proven promising as cancer theranostic tools. Nanoparticles are selective in nature, have reduced toxicity, and controllable drug release patterns making them ideal carriers for anticancer drugs. Numerous nanocarriers have been designed to combat malignancies, including liposomes, micelles, dendrimers, solid nanoparticles, quantum dots, gold nanoparticles, and, more recently, metal-organic frameworks. The temporal and spatial release of therapeutic agents from these nanostructures can be controlled using internal and external triggers, including pH, enzymes, redox, temperature, magnetic and electromagnetic waves, and ultrasound. Ultrasound is an attractive modality because it is non-invasive, can be focused on the diseased site, and has a synergistic effect with anticancer drugs. CONCLUSION: The functionalization of micellar and liposomal surfaces with targeting moieties and the use of ultrasound as a triggering mechanism can help improve the selectivity and enable the spatiotemporal control of drug release from nanocarriers.

Ultrasound-Triggered Immunotherapy for Cancer Treatment: An Update.

Over the past few decades, immunotherapy has emerged as a promising therapeutic approach to treat some types of cancer. Moreover, antibody-based cancer therapies can trigger apoptosis and cell growth inhibition to induce immune cell destruction of target cells through antibody-dependent cellular cytotoxicity (ADCC). Nevertheless, immunotherapeutic efficiency is often restricted due to deficient delivery or low accumulation of therapeutic molecules at the tumor site. The development of pegylated liposomes with monoclonal antibodies conjugated to their surfaces (immunoliposomes) and triggered with ultrasound can effectively improve drug accessibility by enhancing cell membrane permeability and drug release. This review summarizes existing traditional cancer treatments and their limitations, emphasizing the recent advancements in ultrasound-triggered immunotherapy.

Reduced Expression of Chl1 gene Impairs Insulin Secretion by Down-Regulating the Expression of Key Molecules of ß-cell Function.

Silencing of Chl1 gene expression has been previously reported to reduce insulin secretion. Nevertheless, the mechanism underlying this effect remains unclear. In this study, we performed a serial of studies to investigate how Chl1 affects insulin secretion in INS-1 cells. RNA-sequencing was used to investigate the expression of CHL1 in human adipose, liver, muscle, and human islets. Silencing of Chl1 in INS-1 cells was done to assess its impact on the insulin secretion, content, cell viability, and apoptosis. In addition, gene set enrichment analysis (GSEA) was performed to identify possible molecular signatures that associate with Chl1 expression silencing.RNA sequencing data revealed a high expression of CHL1 in pancreatic islets and adipose tissues compared to liver and muscles tissues. Diabetic islets exhibited a lower expression of CHL1 as compared to non-diabetic islets. CHL1 expression was found to correlate positively with insulin secretory index, GLP1R but inversely with HbA1c and BMI. Silencing of Chl1 in INS-1 cells markedly reduced insulin content and secretion. The expression of key molecules of ß-cell function including Insulin, Pdx1, Gck, Glut2, and Insrß was down-regulated in Chl1-silenced cells at transcriptional and translational levels. Cell viability, apoptosis, and proliferation rate were not affected. GSEA showed that the insulin-signaling pathway was influenced in Chl1-silenced cells. Silencing of Chl1 impairs ß-cell function by disrupting the activity of key signaling pathways of importance for insulin biosynthesis and secretion.

Dimethyloxalylglycine (DMOG) and the Caspase Inhibitor "Ac-LETD-CHO" Protect Neuronal ND7/23 Cells of Gluocotoxicity.

It well known that long-lasting hyperglycaemia disrupts neuronal function and leads to neuropathy and other neurodegenerative diseases. The α-ketoglutarate analogue (DMOG) and the caspase-inhibitor "Ac-LETD-CHO are potential neuroprotective molecules. Whether their protections may also extend glucotoxicity-induced neuropathy is not known. Herein, we evaluated the possible cell-protective effects of DMOG and Ac-LETD-CHO against hyperglycaemia-induced reactive oxygen species and apoptosis in ND7/23 neuronal cells. The impact of glucotoxicity on the expression of HIF-1α and a panel of micro-RNAs of significance in hyperglycaemia and apoptosis was also investigated.ND7/23 cells cultured under hyperglycaemic conditions showed decreased cell viability and elevated levels of ROS production in a dose- and time-dependent manner. However, presence DMOG (500 µM) and/or Ac-LETD-CHO (50 µM) counteracted this effect and increase cell viability concomitant with reduction in ROS production, DNA damage and apoptosis. AcLETD-CHO suppressed hyperglycaemia-induced caspase 3 activation in ND7/23 cells. Both DMOG and Ac-LETD-CHO increased HIF-1α expression paralleled with the suppression of miR-126-5p, miR-128-3p and miR-181 expression and upregulation of miR-26b, 106a-5p, 106b-5p, 135a-5p, 135b-5p, 138-5p, 199a-5p, 200a-3p and 200c-3p expression.We demonstrate a mechanistic link for the DMOG and Ac-LETD-CHO protection against hyperglycaemia-induced neuronal dysfunction, DNA damage and apoptosis and thereby propose that pharmacological agents mimicking these effects may represent a promising novel therapy for the hyperglycaemia-induced neuropathy.

Ultrasound-triggered herceptin liposomes for breast cancer therapy.

The functionalization of liposomes with monoclonal antibodies is a potential strategy to increase the specificity of liposomes and reduce the side-effects associated with chemotherapeutic agents. The active targeting of the Human Epidermal growth factor Receptor 2 (HER2), which is overexpressed in HER2 positive breast cancer cells, can be achieved by coating liposomes with an anti-HER2 monoclonal antibody. In this study, we synthesized calcein and Doxorubicin-loaded immunoliposomes functionalized with the monoclonal antibody Trastuzumab (TRA). Both liposomes were characterized for their size, phospholipid content and antibody conjugation. Exposing the liposomes to low-frequency ultrasound (LFUS) triggered drug release which increased with the increase in power density. Trastuzumab conjugation resulted in enhancing the sensitivity of the liposomes to LFUS. Compared to the control liposomes, TRA-liposomes showed higher cellular toxicity and higher drug uptake by the HER2 + cell line (SKBR3) which was further improved following sonication with LFUS. Combining immunoliposomes with LFUS is a promising technique in the field of targeted drug delivery that can enhance efficiency and reduce the cytotoxicity of antineoplastic drugs.

Identification of Novel Hypothalamic MicroRNAs as Promising Therapeutics for SARS-CoV-2 by Regulating ACE2 and TMPRSS2 Expression: An In Silico Analysis.

BACKGROUND: Neuroinvasion of severe acute respiratory syndrome coronavirus (SARS-CoV) is well documented and, given the similarities between this virus and SARS-CoV-2, it seems that the neurological impairment that is associated with coronavirus disease 2019 (COVID-19) is due to SARS-CoV-2 neuroinvasion. Hypothalamic circuits are exposed to the entry of the virus via the olfactory bulb and interact centrally with crucial respiratory nuclei. Hypothalamic microRNAs are considered as potential biomarkers and modulators for various diseases and future therapeutic targets. The present study aims to investigate the microRNAs that regulate the expression of hypothalamic angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2), essential elements for SARS-CoV-2 cell entry. METHODS: To determine potential hypothalamic miRNAs that can directly bind to ACE2 and TMPRSS2, multiple target bioinformatics prediction algorithms were used, including miRBase, Target scan, and miRWalk2.029. RESULTS: Our in silico analysis has revealed that, although there are over 5000 hypothalamic miRNAs, around 31 miRNAs and 29 miRNAs have shown binding sites and strong binding capacity against ACE2 and TMPRSS2, respectively. CONCLUSION: These novel potential hypothalamic miRNAs can be used to identify new therapeutic targets to treat neurological symptoms in COVID-19 patients via regulation of ACE2 and TMPRSS2 expression.

Facile Ultrasound-Triggered Release of Calcein and Doxorubicin from Iron-Based Metal-Organic Frameworks.

Metal-organic frameworks (MOFs) are promising new nanocarriers with potential use in anticancer drug delivery. However, there is a scarcity of studies on the uptake and release of guest molecules associated with MOF nanovehicles, and their mechanism is poorly understood. In this work, newly developed iron-based MOFs, namely Fe-NDC nanorods, were investigated as potential nanocarriers for calcein (as a model drug/dye) and Doxorubicin (a chemotherapeutic drug (DOX)). Calcein was successfully loaded by equilibrating its solution with the MOFs nanoparticles under constant stirring. The calcein average encapsulation efficiency achieved was 43.13%, with a corresponding capacity of 17.74 wt.%. In-vitro calcein release was then carried out at 37°C in phosphate buffer saline (PBS) using ultrasound (US) as an external trigger. MOFs released an average of 17.8% (without US), whereas they released up to 95.2% of their contents when 40-kHz US at ~1 W/cm² was applied for 10 min. The Cytotoxic drug DOX was also encapsulated in Fe-NDC, and its In-vitro release profile was determined under the same conditions. DOX encapsulation efficiency and capacity were found to be 16.10% and 13.37 wt.%, respectively. In-vitro release experiments demonstrated significant release, reaching 80% in 245 minutes, under acoustic irradiation, compared to around 6% in the absence of US. Additionally, experimental results showed that Fe-NDC nanoparticles are biocompatible even at relatively high concentrations, with an MCF-7 IC50 of 1022 g/ml. Our work provides a promising platform for anticancer drug delivery by utilizing biocompatible Fe-NDC nanoparticles and US as an external trigger mechanism.

Potential role of hypothalamic microRNAs in regulation of FOS and FTO expression in response to hypoglycemia.

Hypoglycemia-associated autonomic failure (HAAF) is a serious complication of diabetes which is associated with the absence of physiological homeostatic counter-regulatory mechanisms that are controlled by the hypothalamus and sympathetic nervous system. Identification of biomarkers for early detection of HAAF requires an advanced understanding of molecular signature of hypoglycemia which is yet to be identified. The outcomes of the present study have shown that the viability and the apoptotic rate of the hypothalamic neurons (mHypoE-N39) were decreased significantly due to hypoglycemia in a dose-dependent fashion (p < 0.05). Although there are more than 1000 miRNAs differentially expressed in hypothalamus, only twelve miRNAs (miR-7a, miR-7b, miR-9, miR-29b, miR-29c, miR-30a, miR-30b, miR-30c, miR-101b-3p, miR-181a-5p, miR-378-3p and miR-873-5p) were correlated to two main hypothalamic regulatory proteins, FOS and FTO. Expression of these proteins was very sensitive to hypoglycemia. We demonstrated that hypoglycemia modulates the expression of hypothalamic miRNAs that are related to FOS and FTO.

GNAS gene is an important regulator of insulin secretory capacity in pancreatic ß-cells.

BACKGROUND: Type 2 diabetes (T2D) is a complex polygenic disease with unclear mechanism. In an attempt to identify novel genes involved in ß-cell function, we harness a bioinformatics method called Loss-of-function tool (LoFtool) gene score. METHODS: RNA-sequencing data from human islets were used to cross-reference genes within the 1st quartile of most intolerant LoFtool score with the 100th most expressed genes in human islets. Out of these genes, GNAS and EEF1A1 genes were selected for further investigation in diabetic islets, metabolic tissues along with their correlation with diabetic phenotypes. The influence of GNAS and EEF1A1 on insulin secretion and ß-cell function were validated in INS-1 cells. RESULTS: A comparatively higher expression level of GNAS and EEF1A1 was observed in human islets than fat, liver and muscle tissues. Furthermore, diabetic islets displayed a reduced expression of GNAS, but not of EEF1A, compared to non-diabetic islets. The expression of GNAS was positively correlated with insulin secretory index, GLP1R, GIPR and inversely correlated with HbA1c. Diabetic human islets displayed a reduced cAMP generation and insulin secretory capacity in response to glucose. Moreover, siRNA silencing of GNAS in INS-1 cells reduced insulin secretion, insulin content, and cAMP production. In addition, the expression of Insulin, PDX1, and MAFA was significantly down-regulated in GNAS-silenced cells. However, cell viability and apoptosis rate were unaffected. CONCLUSION: LoFtool is a powerful tool to identify genes associated with pancreatic islets dysfunction. GNAS is a crucial gene for the ß-cell insulin secretory capacity.

Reduced Expression of PLCXD3 Associates With Disruption of Glucose Sensing and Insulin Signaling in Pancreatic ß-Cells.

Previous work has shown that reduced expression of PLCXD3, a member of the phosphoinositide-specific phospholipases (PI-PLC) family, impaired insulin secretion with an unclear mechanism. In the current study, we aim to investigate the mechanism underlying this effect using human islets and rat INS-1 (832/13) cells. Microarray and RNA sequencing data showed that PLCXD3 is among the highly expressed PI-PLCs in human islets and INS-1 (832/13) cells. Expression of PLCXD3 was reduced in human diabetic islets, correlated positively with Insulin and GLP1R expression and inversely with the donor's body mass index (BMI) and glycated hemoglobin (HbA1c). Expression silencing of PLCXD3 in INS-1 (832/13) cells was found to reduce glucose-stimulated insulin secretion (GSIS) and insulin content. In addition, the expression of Insulin, NEUROD1, GLUT2, GCK, INSR, IRS2, and AKT was downregulated. Cell viability and apoptosis rate were unaffected. In conclusion, our data suggest that low expression of PLCXD3 in pancreatic ß-cells associates with downregulation of the key insulin signaling and insulin biosynthesis genes as well as reduction in glucose sensing.

Regulation of Cell Proliferation and Migration by miR-203 via GAS41/miR-10b Axis in Human Glioblastoma Cells.

Glioma amplified sequence 41(GAS41) is a potent transcription factor that play a crucial role in cell proliferation and survival. In glioblastoma, the expression of GAS41 at both transcriptional and post transcriptional level needs to be tightly maintained in response to cellular signals. Micro RNAs (miRNA) are small non coding RNA that act as important regulators for modulating the expression of various target genes. Studies have shown that several miRNAs play role in the post-transcriptional regulation of GAS41. Here we identified GAS41 as a novel target for endogenous miR-203 and demonstrate an inverse correlation of miR-203 expression with GAS41 in glioma cell lines (HNGC2 and U87). Over expression of miR-203 negatively regulates GAS41 expression in U87 and HNGC2 cell lines. Moreover, miR-203 restrained miR-10b action by suppressing GAS41. GAS41 is essential for repressing p53 in tumor suppressor pathway during cell proliferation. Enforced expression of GAS41 produced contradictory effect on miR-203 but was able to enhance p53 tumor suppressor pathway associated protein. It was also found that miR-203 maintains the stability of p53 as knock down of p53 expression using siRNA resulted in down regulation of pri-miR and mature miR-203 expression. Conversely reconstitution of miR-203 expression induced apoptosis and inhibited migratory property of glioma cells. Taken together, we show that miR-203 is a key negative regulator of GAS41 and acts as tumor suppressor microRNA in glioma.

HDAC inhibitor misprocesses bantam oncomiRNA, but stimulates hid induced apoptotic pathway.

Apoptosis or programmed cell death is critical for embryogenesis and tissue homeostasis. Uncontrolled apoptosis leads to different human disorders including immunodeficiency, autoimmune disorder and cancer. Several small molecules that control apoptosis have been identified. Here, we have shown the functional role of triazole derivative (DCPTN-PT) that acts as a potent HDAC inhibitor and mis-express proto onco microRNA (miRNA) bantam. To further understanding the mechanism of action of the molecule in apoptotic pathway, a series of experiments were also performed in Drosophila, a well known model organism in which the nature of human apoptosis is very analogous. DCPTN-PT mis processes bantam microRNA and alters its down regulatory target hid function and cleavage of Caspase-3 which in turn influence components of the mitochondrial apoptotic pathway in Drosophila. However regulatory microRNAs in other pro-apoptotic genes are not altered. Simultaneously, treatment of same molecule also affects the mitochondrial regulatory pathway in human tumour cell lines suggesting its conservative nature between fly and human. It is reasonable to propose that triazole derivative (DCPTN-PT) controls bantam oncomiRNA and increases hid induced apoptosis and is also able to influence mitochondrial apoptotic pathway.

Synthesis and biological evaluation of novel Mannich bases of 2-arylimidazo[2,1-b]benzothiazoles as potential anti-cancer agents.

A new series of Mannich bases of 2-arylimidazo[2,1-b]benzothiazoles were synthesized and evaluated for their anti-cancer activity. These compounds showed better cytotoxicity activity with IC(50) values ranging from 2.8 to 8.0 µM in HepG2, MCF-7 and HeLa cell lines. Further mechanism aspects responsible for the anti-cancer activity of two promising compounds 3c and 3f in HepG2 cell line were studied. Interestingly, 3c, 3f induced G2/M cell cycle arrest with down regulation of cyclin B and up regulation of Chk2 protein. Moreover, compounds 3c, 3f also showed the characteristic features of apoptosis such as enhancement in the levels of caspase-3. Treatments with compounds led to a decrease in levels of vital cell proliferation proteins such as Jun (C-Jun, JunB), p38 MAPK, p-JNK and PKCα. The compound 3f of the series could be considered as the potential lead for its development as a novel anti-cancer agent.