A loss-of-function mutation in KCNJ11 causing sulfonylurea-sensitive diabetes in early adult life.

AIMS/HYPOTHESIS: The ATP-sensitive potassium (KATP) channel couples beta cell electrical activity to glucose-stimulated insulin secretion. Loss-of-function mutations in either the pore-forming (inwardly rectifying potassium channel 6.2 [Kir6.2], encoded by KCNJ11) or regulatory (sulfonylurea receptor 1, encoded by ABCC8) subunits result in congenital hyperinsulinism, whereas gain-of-function mutations cause neonatal diabetes. Here, we report a novel loss-of-function mutation (Ser118Leu) in the pore helix of Kir6.2 paradoxically associated with sulfonylurea-sensitive diabetes that presents in early adult life. METHODS: A 31-year-old woman was diagnosed with mild hyperglycaemia during an employee screen. After three pregnancies, during which she was diagnosed with gestational diabetes, the patient continued to show elevated blood glucose and was treated with glibenclamide (known as glyburide in the USA and Canada) and metformin. Genetic testing identified a heterozygous mutation (S118L) in the KCNJ11 gene. Neither parent was known to have diabetes. We investigated the functional properties and membrane trafficking of mutant and wild-type KATP channels in Xenopus oocytes and in HEK-293T cells, using patch-clamp, two-electrode voltage-clamp and surface expression assays. RESULTS: Functional analysis showed no changes in the ATP sensitivity or metabolic regulation of the mutant channel. However, the Kir6.2-S118L mutation impaired surface expression of the KATP channel by 40%, categorising this as a loss-of-function mutation. CONCLUSIONS/INTERPRETATION: Our data support the increasing evidence that individuals with mild loss-of-function KATP channel mutations may develop insulin deficiency in early adulthood and even frank diabetes in middle age. In this case, the patient may have had hyperinsulinism that escaped detection in early life. Our results support the importance of functional analysis of KATP channel mutations in cases of atypical diabetes.

The impact of ATP-sensitive potassium channel modulation on mitochondria in a Parkinson's disease model using SH-SY5Y cells depends on their differentiation state.

Inward rectifying potassium channels sensitive to ATP levels (KATP) have been the subject of investigation for several decades. Modulators of KATP channels are well-established treatments for metabolic as well as cardiovascular diseases. Experimental studies have also shown the potential of KATP modulation in neurodegenerative disorders. However, to date, data regarding the effects of KATP antagonists/agonists in experiments related to neurodegeneration remain inconsistent. The main source of confusion in evaluating available data seems to be the choice of experimental models. The present study aims to provide a comprehensive understanding of the effects of both opening and blocking KATP channels in two forms of SH-SY5Y cells. Our results offer valuable insights into the significance of metabolic differences between differentiated and non-differentiated SH-SY5Y cells, particularly in the context of glibenclamide and diazoxide effects under normal conditions and during the initiation of pathological events simulating Parkinson's disease in vitro. We emphasize the analysis of mitochondrial functions and changes in mitochondrial network morphology. The heightened protein expression of KATP channels identified in non-differentiated SH-SY5Y cells seems to be a platform for a more significant impact of KATP modulators in this cell type. The efficiency of rotenone treatment in inducing morphological changes in the mitochondrial network depends on the differentiation status of SH-SY5Y cells.

Spectroscopic characterization and pharmacokinetic evaluation of amorphous solid dispersions of glibenclamide for bioavailability enhancement in Wistar rats.

Oral bioavailability of glibenclamide (Glb) was appreciably improved by the formation of an amorphous solid dispersion with Poloxamer-188 (P-188). Poloxamer-188 substantially enhanced the solubility and thereby the dissolution rate of the biopharmaceutics classification system (BCS) class II drug Glb and simultaneously exhibited a better stabilizing effect of the amorphous solid dispersion prepared by the solvent evaporation method. The physical state of the dispersed Glb in the polymeric matrix was characterized by differential scanning calorimetry, X-ray diffraction, scanning electron microscope and Fourier transform infrared studies. In vitro drug release in buffer (pH 7.2) revealed that the amorphous solid dispersion at a Glb-P-188 ratio of 1:6 (SDE4) improved the dissolution of Glb by 90% within 3 h. A pharmacokinetic study of the solid dispersion formulation SDE4 in Wistar rats showed that the oral bioavailability of the drug was greatly increased as compared with the market tablet formulation, Daonil®. The formulation SDE4 resulted in an AUC0-24h ~2-fold higher. The SDE4 formulation was found to be stable during the study period of 6 months.

Efficacy and Safety of Early Treatment with Glibenclamide in Patients with Aneurysmal Subarachnoid Hemorrhage: A Randomized Controlled Trial.

BACKGROUND: This study aims to investigate the efficacy and safety of glibenclamide treatment in patients with acute aneurysmal subarachnoid hemorrhage (aSAH). METHODS: The randomized controlled trial was conducted from October 2021 to May 2023 at two university-affiliated hospitals in Beijing, China. The study included patients with aSAH within 48 h of onset, of whom were divided into the intervention group and the control group according to the random number table method. Patients in the intervention group received glibenclamide tablet 3.75 mg/day for 7 days. The primary end points were the levels of serum neuron-specific enolase (NSE) and soluble protein 100B (S100B) between the two groups. Secondary end points included evaluating changes in the midline shift and the gray matter-white matter ratio, as well as assessing the modified Rankin Scale scores during follow-up. The trial was registered at ClinicalTrials.gov (identifier NCT05137678). RESULTS: A total of 111 study participants completed the study. The median age was 55 years, and 52% were women. The mean admission Glasgow Coma Scale was 10, and 58% of the Hunt-Hess grades were no less than grade III. The baseline characteristics of the two groups were similar. On days 3 and 7, there were no statistically significant differences observed in serum NSE and S100B levels between the two groups (P > 0.05). The computer tomography (CT) values of gray matter and white matter in the basal ganglia were low on admission, indicating early brain edema. However, there were no significant differences found in midline shift and gray matter-white matter ratio (P > 0.05) between the two groups. More than half of the patients had a beneficial outcome (modified Rankin Scale scores 0-2), and there were no statistically significant differences between the two groups. The incidence of hypoglycemia in the two groups were 4% and 9%, respectively (P = 0.439). CONCLUSIONS: Treating patients with early aSAH with oral glibenclamide did not decrease levels of serum NSE and S100B and did not improve the poor 90-day neurological outcome. In the intervention group, there was a visible decreasing trend in cases of delayed cerebral ischemia, but no statistically significant difference was observed. The incidence of hypoglycemia did not differ significantly between the two groups.

Evaluation of serum pro/anti-angiogenic biomarkers in hyperglycemic rats treated with Securigera securidaca seeds, alone and in combination with Glibenclamide.

Introduction: Herbal medicines are commonly used by many people with diabetes in addition to standard treatment. Plants contain numerous known and unknown compounds that may exacerbate or ameliorate diabetes complications. Therefore, it is crucial to be aware of the side effects of these herbs before prescribing them. This study aimed to investigate the effects of hydroalcoholic extracts of Securigera securidaca (HESS) seeds alone and in combination with glibenclamide on the angiogenic/anti-angiogenic balance in streptozotocin (STZ)-induced diabetic rats. Methods: Groups involved in this animal study included diabetic and healthy controls, three doses of HESS, glibenclamide, and combination therapy. Serum samples were collected and analyzed for a vascular endothelial growth factor (VEGF), fibroblast growth factor 21 (FGF21), fetal liver kinase 1 (FLK-1), soluble fms-like tyrosine kinase 1 (sFLT-1), and transforming growth factor -beta (TGF-ß). Results: Induction of diabetes increased VEGF, FGF21, and TGF-ß serum levels and decreased circulating FLK-1 and sFLT-1 factors. Herbal extract, except TGF-ß, had little effect on the above blood levels even at the highest doses. Glibenclamide was more effective than the highest dose of HESS in improving the vascular complications of diabetes. Combination therapy with the highest dose of HESS partly enhanced the glibenclamide effects. Conclusion: Compared with glibenclamide as a standard chemical drug, HESS had no significant effects on the blood levels of the pro/anti-angiogenesis factor in diabetic rats. Glibenclamide attenuated the levels of the biomarkers and its effects were somewhat enhanced in combination with the highest dose of HESS.

Vascular contraction of umbilical arteries of pregnant women with preeclampsia.

Objective: Potassium channels have an important role in the vascular adaptation during pregnancy and a reduction in the expression of adenosine triphosphate-sensitive potassium channels (Katp) has been linked to preeclampsia. Activation of Katp induces vasodilation; however, no previous study has been conducted to evaluate the effects of the inhibition of these channels in the contractility of preeclamptic arteries. Glibenclamide is an oral antihyperglycemic agent that inhibits Katp and has been widely used in vascular studies. Methods: To investigate the effects of the inhibition of Katp, umbilical arteries of preeclamptic women and women with healthy pregnancies were assessed by vascular contractility experiments, in the presence or absence of glibenclamide. The umbilical arteries were challenged with cumulative concentrations of potassium chloride (KCl) and serotonin. Results: There were no differences between the groups concerning the maternal age and gestational age of the patients. The percentage of smokers, caucasians and primiparae per group was also similar. On the other hand, blood pressure parameters were elevated in the preeclamptic group. In addition, the preeclamptic group presented a significantly higher body mass index. The newborns of both groups presented similar APGAR scores and weights. Conclusion: In the presence of glibenclamide, there was an increase in the KCl-induced contractions only in vessels from the PE group, showing a possible involvement of these channels in the disorder.

Implications of NLRP3 Suppression Using Glibenclamide and miR-223 against Colorectal Cancer.

The NLR family pyrin domain containing 3 (NLRP3) promotes the growth of colorectal cancer (CRC). However, the therapeutic effect of NLRP3 inhibition on CRC cell progression is controversial. This study comparatively investigated the therapeutic effect of a pharmacological NLRP3 inhibitor, glibenclamide (gli), and the post-translational suppression of NLRP3 by miR-223 on CRC cell progression in HCT-116 and HCT-15 cells. LPS and ATP were used to activate Gli-treated and LSB-hsa-miR-223-3p (WTmiR-223)-expressing HCT-116 cells. NLRP3.AB.pCCL.sin.cPPT.U6.miR-223-Decoy.hPGK.GFP.WPRE plasmid (DmiR-223) was the negative control for miR-223 expression. NLRP3, gasdermin D, and BAX expressions were analyzed using western blotting. Real-time PCR detected the RNA expression of autophagy-related genes ATG5, BECN1, and miR-223 in non-transfected cells. ELISA analyzed IL-1ß and IL-18 in the medium. MTS-1, annexin V, wound-healing, and sphere-invasion assays were used to assess cell viability and progression. A multiplex cytokine assay detected proinflammatory cytokine secretion. LPS-ATP-activated NLRP3 produced gasdermin D cleavage, released IL-1b and IL-18, and activated cell migration and sphere invasion. In contrast, reduced cell growth, miR-223 expression, IFN-γ, CXCL10, and LIF secretion were found in cells after inflammasome activation. Both gli and WTmiR-223 induced autophagy genes ATG5 and BECN1 and reduced the NLRP3 activation and its downstream proteins. However, while gli had a limited effect on the production of IFN-γ, CXCL10, and LIF, WTmiR-223 increased the release of those cytokines. In addition, gli did not suppress cell growth, while WTmiR-223 promoted apoptosis. Notably, neither gli nor WTmiR-223 effectively prevented sphere invasion. These data suggest that, while WTmiR-223 could have a better anticancer effect in CRC compared to gli, the sole usage of miR-223-mediated NLRP3 suppression may not be sufficient to prevent CRC metastasis.

Investigation of the Cognitive Activity Between the Leaf Extracts of Eclipta alba and Ziziphus jujuba in Diabetic Animal Models.

Diabetes mellitus (DM), a prevalent metabolic disorder, is associated with widespread damage to bodily systems, notably causing significant dysfunction within the peripheral and central nervous systems (CNS). The primary objective of this study is to explore the extent of DM's impact on cognitive and behavioral functions and to evaluate the therapeutic potential of ethanol leaf extracts from Ziziphus jujuba (ZJ) and Eclipta alba (EA) in mitigating these adverse effects. Utilizing an established animal model, we aimed to determine the effectiveness of these plant extracts in ameliorating the cognitive impairments commonly seen in diabetic states. In our experimental framework, we allocated Wistar rats (n=6 per group) into eight different groups, inducing DM through alloxan administration. The intervention groups were treated orally with either the standard antidiabetic drug glibenclamide or varying doses of ZJ and EA extracts over periods of seven and 21 days. Throughout the study, we carefully tracked fluctuations in blood glucose levels, noting considerable decreases, particularly following the 21-day treatment interval. Post-treatment, the rats' cognitive functions were assessed using the Morris water maze (MWM) test. This evaluation revealed significant cognitive enhancement in the diabetic rats administered with ZJ and EA extracts, with these groups displaying reduced latency in finding the submerged platform, indicative of improved learning and memory. These observations were statistically significant (p<0.01). The findings underscore the hypoglycemic effects of ZJ and EA extracts and suggest their viability as cognitive enhancers in the context of DM. The protective effects of these extracts against cognitive decline caused by DM are clear. They add important new information to the research on natural phytochemicals for managing chronic diseases. This study opens new avenues for the application of these substances in treating neurocognitive disorders associated with DM.

Edible mushroom (Pleurotus cornucopiae) extract vs. glibenclamide on alloxan induced diabetes: sub-acute in vivo study of Nrf2 expression and renal toxicity.

The study aims to compare the action of Pleurotus cornucopiae and glibenclamide on alloxan-induced diabetes and ascertain how an aqueous extract of the edible mushroom regulates the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), oxidative stress biomarkers and renal toxicity in a diabetic male Wistar rat model. Twenty-five adult male Wistar rats were randomly grouped into five groups with five rats per. Group 1 and those in the treatment groups received normal feed and water ad libitum. Group 2 received intraperitoneal administration of alloxan monohydrate (150 mg/kg body weight). Group 3 received alloxan monohydrate and glibenclamide (5 mg/kg body weight bwt), group 4 received alloxan monohydrate plus the extract (250 mg/kg bwt) and group 5 received alloxan monohydrate plus the extract (500 mg/kg bwt). The administration of glibenclamide plus the extract was oral for 14 days. Glibenclamide and the extract lowered blood glucose level, catalase, and glutathione peroxidase activities, increased the superoxide dismutase (SOD) activity in rats with alloxan induced diabetes. The extract at 500 mg/kg bwt reduced the plasma urea and sodium concentration in the treated rats. The extract and glibenclamide could detoxify alloxan and restore its induced renal degeneration and glomeruli atrophy, intra renal hemorrhage and inflammation and oxidative biomarkers through activation of Nrf2 expression. The drug glibenclamide and P. cornucopiae have appreciable hypoglycemic activity and potential to restore the normal renal architecture in the rats, hence they offer similar curative effects. Additionally, the extract at 500 mg/kg bwt activated SOD and Nrf2 expression more than glibenclamide in rats with alloxan-induced diabetes.

Novel Activity of Oral Hypoglycemic Agents Linked with Decreased Formation of Tryptophan Metabolite, Kynurenic Acid.

Kynurenic acid is a tryptophan (Trp) metabolite formed along the kynurenine (KYN) pathway in the brain and in peripheral tissues. The disturbed formation of kynurenic acid, which targets glutamate-mediated neurotransmission, GPR35, and aryl hydrocarbon receptors of immune or redox status, was implicated in the development of neuropsychiatric and metabolic disorders among others. Kynurenic acid exerts neuroprotective and immunomodulatory effects, yet its high brain levels may negatively impact cognition. Changes in the Trp-KYN pathway are also linked with the pathogenesis of diabetes mellitus, which is an established risk factor for cardiovascular and neurological diseases or cognitive deficits. Here, the effects of metformin and glibenclamide on the brain synthesis of kynurenic acid were evaluated. Acute exposure of rat cortical slices in vitro to either of the drugs reduced kynurenic acid production de novo. Glibenclamide, but not metformin, inhibited the activity of kynurenic acid biosynthetic enzymes, kynurenine aminotransferases (KATs) I and II, in semi-purified cortical homogenates. The reduced availability of kynurenic acid may be regarded as an unwanted effect, possibly alleviating the neuroprotective action of oral hypoglycemic agents. On the other hand, considering that both compounds ameliorate the cognitive deficits in animal and human studies and that high brain kynurenic acid may hamper learning and memory, its diminished synthesis may improve cognition.

Timed sulfonylurea modulation improves locomotor and sensory dysfunction following spinal cord injury.

Traumatic spinal cord injury (SCI) results in immediate tissue necrosis and delayed secondary expansion of neurological damage, often resulting in lifelong paralysis, neurosensory dysfunction, and chronic pain. Progressive hemorrhagic necrosis (PHN) and excessive excitation are the main sources of secondary neural injury. Recent approaches to attenuate PHN by glibenclamide can improve locomotor function after SCI. However, use of glibenclamide can exacerbate development of SCI-induced chronic pain by inhibiting KATP channels to increase neuronal excitation and glial activation. In this study, we explored a treatment strategy involving administration of glibenclamide, which suppresses PHN, and diazoxide, which protects against neuronal excitation and inflammation, at different time intervals following spinal cord contusion. Our goal was to determine whether this combined approach enhances both sensory and motor function. Contusive SCI was induced at spinal segment T10 in adult rats. We found that KATP channels opener, diazoxide, decreased the hyperexcitability of primary sensory neurons after SCI by electrophysiology. Timed application of glibenclamide and diazoxide following contusion significantly improved locomotor function and mitigated development of SCI-induced chronic pain, as shown by behavioral evidence. Finally, we found that timed application of glibenclamide and diazoxide attenuates the inflammatory activity in the spinal cord and increases the survival of spinal matters following SCI. These preclinical studies introduce a promising potential treatment strategy to address SCI-induced dysfunction.

Nanostructured Lipid Carrier-Mediated Transdermal Delivery System of Glibenclamide for Gestational Diabetes: Pharmacokinetic and Pharmacodynamic Evaluation.

BACKGROUND: Gestational diabetes mellitus (GDM) poses significant risks during pregnancy for both mother and fetus. Adherence to oral antidiabetic medications, like glibenclamide (GB), can be challenging, necessitating novel drug delivery methods. Nanostructured lipid carriers (NLC) offer a promising approach by efficiently permeating the skin due to their small size and lipid-based composition. OBJECTIVE: This study aimed to develop and evaluate transdermal patches loaded with glibenclamide NLCs to treat GDM. METHODS: Glibenclamide NLCs were prepared using hot homogenization with ultrasonication and melt dispersion method. A central composite design was utilized to optimize the formulations. Transdermal patches containing optimized NLCs were developed using HPMC K 100 and Eudragit L polymers. The patches were evaluated for various parameters, and their pharmacokinetic and pharmacodynamic studies were carried out to assess their safety and efficacy. RESULTS: Optimized NLCs efficiently permeated rat skin. Cell viability studies indicated the nontoxicity of the formulations. NLC-loaded transdermal patches (F2 and F7) showed drug release of 1098 µg/cm2 and 1001.83 µg/cm2 in 24 h, with a 2.5-fold higher flux and permeation coefficient than the GB patch. Pharmacokinetic analysis revealed Tmax of 8 and 10 h and Cmax of 7127 ng/ml and 7960 ng/ml for F2 and F7, respectively, ensuring sustained drug action. AUC0-α was 625681 ng/ml·h and 363625 ng/ml·h for F2 and F7, respectively, indicating improved bioavailability. CONCLUSION: Transdermal patches incorporating NLCs hold promise for enhancing glibenclamide's therapeutic efficacy in GDM treatment. Improved skin permeation, sustained drug release, and enhanced bioavailability make NLC-based transdermal patches a potential alternative with better patient compliance.

Pharmacological Basis for the Antidiarrheal and Antispasmodic Effects of Cuminaldehyde in Experimental Animals: In Silico, Ex Vivo and In Vivo Studies.

BACKGROUND: Medicinal herbs are frequently used for the management of gastrointestinal disorders because they contain various compounds that can potentially amplify the intended therapeutic effects. Cuminaldehyde is a plant-based constituent found in oils derived from botanicals such as cumin, eucalyptus, myrrh, and cassia and is responsible for its health benefits. Despite the utilization of cuminaldehyde for several medicinal properties, there is currently insufficient scientific evidence to support its effectiveness in treating diarrhea. Hence, the present investigation was carried out to evaluate the antidiarrheal and antispasmodic efficacy of cuminaldehyde, with detailed pharmacodynamics explored. METHODS: An in vivo antidiarrheal test was conducted in mice following the castor oil-induced diarrhea model, while an isolated small intestine obtained from rats was used to evaluate the detailed mechanism(s) of antispasmodic effects. RESULTS: Cuminaldehyde, at 10 and 20 mg/kg, exhibited 60 and 80% protection in mice from episodic diarrhea compared to the saline control group, whereas this inhibitory effect was significantly reversed in the pretreated mice with glibenclamide, similar to cromakalim, an ATP-dependent K+ channel opener. In the ex vivo experiments conducted in isolated rat tissues, cuminaldehyde reversed the glibenclamide-sensitive low K+ (25 mM)-mediated contractions at significantly higher potency compared to its inhibitory effect against high K+ (80 mM), thus showing predominant involvement of ATP-dependent K+ activation followed by Ca++ channel inhibition. Cromakalim, a standard drug, selectively suppressed the glibenclamide-sensitive low K+-induced contractions, whereas no relaxation was observed against high K+, as expected. Verapamil, a Ca++ channel inhibitor, effectively suppressed both low and high K+-induced contractions with similar potency, as anticipated. At higher concentrations, the inhibitory effect of cuminaldehyde against Ca++ channels was further confirmed when the preincubated ileum tissues with cuminaldehyde (3 and 10 mM) in Ca++ free medium shifted CaCl2-mediated concentration-response curves (CRCs) towards the right with suppression of the maximum peaks, similar to verapamil, a standard Ca++ ion inhibitor. CONCLUSIONS: Present findings support the antidiarrheal and antispasmodic potential of cuminaldehyde, possibly by the predominant activation of ATP-dependent K+ channels followed by voltage-gated Ca++ inhibition. However, further in-depth assays are recommended to know the precise mechanism and to elucidate additional unexplored mechanism(s) if involved.

Oral administration of proniosomal glibenclamide formulation protects testicular tissue from hyperglycemia fluctuations and ROS via Nrf2/HO-1 pathway.

Type 2 diabetes causes high blood sugar due to insulin malfunction and is linked to male infertility. Using proniosomes can enhance the effectiveness of Glibenclamide, a medication that stimulates insulin secretion. In our study, male rats with diabetes were treated with GLB with or without proniosomal for 14 days. Proniosomal formulations maintained glucose levels prevented weight loss and showed normal testicular tissue. GLB-proniosomal reduces ROS caused by T2DM through Nrf2, HO-1 pathway and increases CAT, SOD, and GSH production in response to insulin and glucose uptake. The reference and proniosomal treatments showed CAT and SOD significant enzymatic elevation compared to the positive and negative control. CAT significantly correlated with Gpx4 expression with P = 0.0169 and r = 0.98; similarly, the enzymatic activity of SOD also showed a positive correlation between the average glucose levels (r = 0.99 and P = 0.0037). Intestinally, GSH analysis revealed that only proniosomal-GLB samples are significantly elevated from the positive control, with a P value of 0.0210. The data showed proniosomal-GLB was more effective than pure GLB, confirmed by higher Nrf2 (2.050 folds), HO-1 (2.148 folds), and GPx4 (1.9 folds) transcript levels relative to the control with less sample diversity compared to the reference samples, indicating proniosomal stabilized GLB in the blood. Administering GLB and proniosomes formulation has effectively restored testicular function and sperm production in diabetic rats by regulating ROS levels and upregulating anti-ROS in response to glucose uptake. These findings may lead to better treatments for diabetic patients who have infertility issues.

Glyburide confers neuroprotection against age-related macular degeneration (AMD).

Glyburide, a sulfonylurea drug used to treat type 2 diabetes, boasts neuroprotective effects by targeting the sulfonylurea receptor 1 (SUR1) and associated ion channels in various cell types, including those in the central nervous system and the retina. Previously, we demonstrated that glyburide therapy improved retinal function and structure in a rat model of diabetic retinopathy. In the present study, we explore the application of glyburide in non-neovascular ("dry") age-related macular degeneration (AMD), another progressive disease characterized by oxidative stress-induced damage and neuroinflammation that trigger cell death in the retina. We show that glyburide administration to a human cone cell line confers protection against oxidative stress, inflammasome activation, and apoptosis. To corroborate our in vitro results, we also conducted a case-control study, controlling for AMD risk factors and other diabetes medications. It showed that glyburide use in patients reduces the odds of new-onset dry AMD. A positive dose-response relationship is observed from this analysis, in which higher cumulative doses of glyburide further reduce the odds of new-onset dry AMD. In the quest for novel therapies for AMD, glyburide emerges as a promising repurposable drug given its known safety profile. The results from this study provide insights into the multifaceted actions of glyburide and its potential as a neuroprotective agent for retinal diseases; however, further preclinical and clinical studies are needed to validate its therapeutic potential in the context of degenerative retinal disorders such as AMD.

Glibenclamide-Loaded Engineered Nanovectors (GNVs) Modulate Autophagy and NLRP3-Inflammasome Activation.

Activation of the NLRP3 inflammasome in response to either exogenous (PAMPs) or endogenous (DAMPs) stimuli results in the production of IL-18, caspase-1 and IL-1ß. These cytokines have a beneficial role in promoting inflammation, but an excessive activation of the inflammasome and the consequent constitutive inflammatory status plays a role in human pathologies, including Alzheimer's disease (AD). Autophagic removal of NLRP3 inflammasome activators can reduce inflammasome activation and inflammation. Likewise, inflammasome signaling pathways regulate autophagy, allowing the development of inflammatory responses but preventing excessive and detrimental inflammation. Nanotechnology led to the development of liposome engineered nanovectors (NVs) that can load and carry drugs. We verified in an in vitro model of AD-associated inflammation the ability of Glibenclamide-loaded NVs (GNVs) to modulate the balance between inflammasome activation and autophagy. Human THP1dM cells were LPS-primed and oligomeric Aß-stimulated in the presence/absence of GNVs. IL-1ß, IL-18 and activated caspase-1 production was evaluated by the Automated Immunoassay System (ELLA); ASC speck formation (a marker of NLRP3 activation) was analyzed by FlowSight Imaging flow-cytometer (AMNIS); the expression of autophagy targets was investigated by RT-PCR and Western blot (WB); and the modulation of autophagy-related up-stream signaling pathways and Tau phosphorylation were WB-quantified. Results showed that GNVs reduce activation of the NLRP3 inflammasome and prevent the Aß-induced phosphorylation of ERK, AKT, and p70S6 kinases, potentiating autophagic flux and counteracting Tau phosphorylation. These preliminary results support the investigation of GNVs as a possible novel strategy in disease and rehabilitation to reduce inflammasome-associated inflammation.

Vascular contraction of umbilical arteries of pregnant women with preeclampsia

Abstract Objective: Potassium channels have an important role in the vascular adaptation during pregnancy and a reduction in the expression of adenosine triphosphate-sensitive potassium channels (Katp) has been linked to preeclampsia. Activation of Katp induces vasodilation; however, no previous study has been conducted to evaluate the effects of the inhibition of these channels in the contractility of preeclamptic arteries. Glibenclamide is an oral antihyperglycemic agent that inhibits Katp and has been widely used in vascular studies. Methods: To investigate the effects of the inhibition of Katp, umbilical arteries of preeclamptic women and women with healthy pregnancies were assessed by vascular contractility experiments, in the presence or absence of glibenclamide. The umbilical arteries were challenged with cumulative concentrations of potassium chloride (KCl) and serotonin. Results: There were no differences between the groups concerning the maternal age and gestational age of the patients. The percentage of smokers, caucasians and primiparae per group was also similar. On the other hand, blood pressure parameters were elevated in the preeclamptic group. In addition, the preeclamptic group presented a significantly higher body mass index. The newborns of both groups presented similar APGAR scores and weights. Conclusion: In the presence of glibenclamide, there was an increase in the KCl-induced contractions only in vessels from the PE group, showing a possible involvement of these channels in the disorder.

Ceiling effect of Postconditioning and Atrial Natriuretic Peptide in Cardioprotection against Ischemia Reperfusion Injury in Ovariectomized rat hearts

Abstract Ischemic postconditioning (IPTC) brings cardioprotection endogenously, Atrial natriuretic peptide (ANP) produces the same effect. It happens due to down expression of endothelial nitric oxide synthase (eNOS). Thus, experimental protocol associating IPTC has been formulated to find the role of ANP in the cardioprotection of heart in OVX rats. For this experiment, heart was isolated from OVX rat and held tightly on Langendorff's apparatus in a manner that ischemia of 30 min and reperfusion of 120 min were also given. Simultaneously, IPTC with four cycles of 5 min ischemia and 5 min reperfusion of each was applied. Parameters like size of myocardial infarct, levels of lactate dehydrogenase (LDH) and release of creatine kinase- MB (CK-MB) in coronary effluent were noted after each stage of experiment for ensuring the extent of myocardial injury. Some significant changes were also seen in the histopathology of cardiovascular tissues. The cardio-protection has been made by four cycles of IPTC. It was confirmed by decline in the size of myocardial infarct. It diminishes the release of LDH and CK-MB in heart of OVX rat. Thus, IPTC induces cardio-protection in the isolated heart from OVX rat. Perfusion of ANP associating with IPTC favors the cardioprotection which is further confirmed by rise in the NO release and heart rate. The level of myocardial damage changes using IPTC, IPTC+OVX, IPTC+OVX+ANP, IPTC+ OVX+ANP+L-NAME and other groups were observed significantly and were found to be less than those in I/R control group. Thus, it is recommended that ANP involving IPTC restores attenuated cardio-protection in OVX rat heart. Therefore, Post-conditioning is useful in various clinical aspects.

Determination of structural properties in the adsorption of drugs on chitosan-hydrogels for type 2 diabetes by means of the PM6 method / Determinación de propiedades estructurales en la adsorción de fármacos en hidrogeles de quitosano para diabetes tipo 2 mediante el método PM6 / Determinação das propriedades estruturais en adsorção de drogas em hidrogelos de quitosan para diabetes do tipo 2 pelo método PM6

Abstract Computational chemistry performs the modeling and calculation of physicochemical properties that allow understanding of the different molecular interactions at the nanometric scale in medical applications such as the design of controlled release systems. The PM6 model was used to analyze metformin and glibenclamide. First, the energy properties as the Gibbs free energy and enthalpies were obtained. The results showed the affinity of both drugs with water (glibenclamide: -7.96 and metformin: -11.49) due to the formation of hydrogen bonds, which were verified by the electronegativities corresponding to the dipole moment and to the partition coefficient (Log P). Subsequently, the main properties for the design of a release system using the metformin/glibenclamide complex in the chitosan hydrogel were determined. In this process it was appreciated that the Gibbs free energy (-2157.60 kcal/ mol) determined the thermodynamic stability of the adsorption. In addition, the Log P (-25.82) indicated an instantaneous solubility through the formation of hydrogen bonds and were verified by the electronic distribution and the change in dipole moment.

Resumen La química computacional realiza el modelado y el cálculo de propiedades fisicoquímicas que permiten comprender las diferentes interacciones moleculares a escala nanométrica en aplicaciones médicas como el diseño de sistemas de liberación controlada, por ejemplo. El modelo PM6 se utilizó para analizar metformina y glibenclamida. Primero se obtuvieron las propiedades energéticas como la energía libre de Gibbs y las entalpias. Los resultados mostraron la afinidad de ambos fármacos con el agua (glibenclamide: -7,96 y metformina: -11,49) debido a la formación de enlaces de hidrógeno que fueron verificados por las electronegatividades correspondientes al momento dipolar y al coeficiente de partición (Log P). Posteriormente, se determinaron las principales propiedades para el diseño de un sistema de liberación que usa el complejo metformina/glibenclamida en el hidrogel de quitosano. En este proceso se apreció que la energía libre de Gibbs (-2157,60 kcal/mol) determinó la estabilidad termodinámica de la adsorción. Además, el Log P (-25,82) indicó una solubilidad instantánea a través de la formación de enlaces de hidrógeno y se verificó mediante la distribución electrónica y el cambio en el momento dipolar.

Resumo A química computacional realiza a modelagem e o cálculo das propriedades físico-químicas que permitem compreender as diferentes interações moleculares em escala nanométrica em aplicações médicas, como o projeto de sistemas de liberação controlada. O modelo PM6 é usado para analisar metformina e glibenclamida. Primeiro, obtenha as propriedades energéticas como a energia livre de Gibbs e as entalpias. Os resultados mostram a afinidade de ambos os componentes com água (glibenclamida: -7.96 e forma: -11.49) debitados na forma de ligações de hidrogénio, que verificam por eletronegatividades correspondentes no momento dipolar e coeficiente de participação (Log P). Posteriormente, selecione as principais propriedades para o projeto de um sistema de liberação que usa o método completo/glibenclamida no hidrogel de quitosano. Neste processo, aprecie a energia livre de Gibbs (-2157.60 kcal/mol) que determina a estabilidade termodinâmica da adsorção. Além disso, o Log P (-25.82) indica uma solução instantânea para a passagem de forma de hidrogénio e é verificada usando a distribuição eletrônica e o câmbio no momento dipolar.

Influence of silymarin and chromium picolinate on the pharmacotherapy of rats with induced diabetes / Influência da silimarina e picolinato de cromo na farmacoterapia de ratos com diabetes induzida

SUMMARY Food supplements are easily acquired and used in various countries. Silymarin has been indicated for diseases of the liver and Chromium picolinate has been indicated for body weight loss and for the improvement of glycemic index. The objective of the present study was to assess the effects of short-term treatment with a combination of silymarin (50 mg/kg) and chromium picolinate (5 µg/kg) on the standard glibenclamide treatment (10 mg/kg) of rats with induced diabetes. DM2 was induced with streptozotocin. Experimental groups of rats: healthy control group, glibenclamide diabetic group, silymarin diabetic group, and silymarin, chromium picolinate and glibenclamide group. After 10 days of oral treatment, we determined body weight, fasting glycemia, glycemia 1 h after gastric gavage with sucrose, and AST and ALT transaminases. Statistical analysis of the data indicated that there was no change in body weight or fasting glycemia, but that glycemia increased after gavage with sucrose in the group submitted to combined therapy. Thus, we concluded that the combination of silymarin and chromium picolinate reduced the efficacy of glibenclamide in the short term, although the two substances had a protective effect on the liver as observed by the reduction of blood transaminase levels.

RESUMO Suplementos alimentares são de fácil aquisição e uso em diversos países. A silimarina tem sido indicada para desordens hepáticas e o picolinato de cromo tem sido utilizado para perda de peso corporal e melhoria do índice glicêmico. O objetivo deste trabalho foi avaliar os efeitos do tratamento utilizando uma combinação de silimarina (50 mg/kg) e picolinato de cromo (5 µg/kg) sobre o tratamento com glibencla-mida (10 mg/kg) em ratos com diabetes induzida com estreptozotocina. Os grupos experimentais foram: grupo controle sadio, grupo diabético glibenclamida, grupo diabético silimarina e grupo diabético silimarina, picolinato de cromo e glibencla-mida. Após 10 dias de tratamento via oral, determinou-se o peso corpóreo, glicemia de jejum, glicemia após uma hora de gavagem gástrica com sacarose e transaminases hepáticas. A análise estatística dos dados indicou que não ocorreu alteração significativa no peso corpóreo e na glicemia de jejum, mas ocorreu aumento significativo dos níveis glicêmicos no grupo diabético silimarina, picolinato de cromo e glibenclamida após a gavagem com sacarose no grupo com a terapia combinada. Portanto, conclui-se que a combinação utilizada reduziu a eicácia da glibenclamida em curto prazo, embora ambas substancias tenham exibido efeito hepatoprotetor, observado pela redução dos níveis plasmáticos de transaminases.