bluuebunny/crossref_metadata_2025_split huggingface dataset:
Calorie Restriction Mimicking by Isoliquiritigenin Attenuates Experimental Diabetic Neuropathy via Induction of Mitochondrial Biogenesis and Autophagy
Authors: Yerra Veera Ganesh , Kalvala Anil Kumar , Kumar Ashutosh 
Published: November 2023

ObjectiveThe current study assessed the pharmacological efficacy of SIRT1 activation by a natural compound, Isoliquiritigenin (ILQ) in experimental models of Streptozotocin (STZ) induced diabetic neuropathy (DN) and high glucose induced neurotoxicity in neuro2a cells.Materials & methodsILQ was administered at doses of 10 mg/kg and 20 mg/kg to the diabetic animals during 7th& 8thweek after diabetes induction (STZ 55mg/kg, i.p). Animals were subjected to assessment of tactile sensitivity to temperature stimuli and mechanical stimuli. Motor nerve conduction velocity (MNCV), sensory nerve conduction velocity (SNCV) and Sciatic nerve blood flow (NBF) were determined for functional assessment of neuropathic severity. Sciatic nerves were homogenized for biochemical estimations and western blotting analysis. Nerve sections were processed for tunel assay. For in vitro studies, Neuro2a cells were used and incubated with MEM media containing 25mM glucose to simulate high glucose condition. Cells were treated with ILQ (2.5 & 5 μM) for 24 hrs and then analyzed for reactive oxygen species (ROS) generation, mitochondrial superoxide generation, neurite growth analysis and western blotting analysis.ResultsILQ administration for 2 weeks ameliorated the diabetes induced hyperalgesia and allodynia as evident from the enhanced tail withdrawal latencies to temperature stimuli and increased paw withdrawal responses to mechanical stimuli in ILQ treated rats. ILQ administration also enhanced MNCV, SNCV and NBF in the diabetic animals. ILQ exposure to neuro2a cells reduced the high glucose induced ROS, superoxide generation and enhanced neurite length. Tunel assay and biochemical analysis showed that ILQ treatment reduced oxidative biomolecular damage by enhancing antioxidant defenses. ILQ treatment also enhanced the reductive NAD pool required for oxidative phosphorylation mediated energy production in the sciatic nerves. Western blotting analysis has shown that ILQ treatment ameliorated the diabetes induced impairment in mitochondrial biogenesis and autophagy through PGC‐1α induction and mTOR inhibition respectively.ConclusionILQ through SIRT1 activation improved mitochondrial biogenesis and autophagic turnover in neuronal cells and imparted mitochondrial protection. Pharmacological modulators of SIRT1 and associated mitochondrial signaling can be developed as potential therapeutic choice for the management of DN.Support or Funding InformationDepartment of Pharmaceuticals, Ministry of Chemicals and Fertilizers, Government of India.
Rapid Antidepressant‐like Effects of the “Uptake‐2” Blocker, Decynium 22 in the Flinders Sensitive Line Rat Model of Depression
Authors: Fraser‐Spears Rheaclare , Owens W. Anthony , Mitchell Nathan C , Overstreet David , Koek Wouter , Daws Lynette C 
Published: November 2023

BackgroundSelective serotonin reuptake inhibitors (SSRIs) are widely prescribed to treat major depression and mood disorders, however, many patients report low to no symptom relief with SSRI treatment. We found that activity of low‐affinity, high‐capacity (uptake 2) transporters for biogenic amines, in particular organic cation transporter 3 (OCT3), may limit therapeutic efficacy of SSRIs. Moreover, in C56BL/6 mice we found that decynium‐22 (D22), which blocks OCT1, OCT2, OCT3 and the plasma membrane monoamine transporter (PMAT), produced antidepressant‐like effects when the serotonin transporter was either pharmacologically or genetically compromised. These studies point to D22 sensitive transporters, putatively OCT3, as a promising target for development of new therapeutics for depression. Here, we expand these studies to examine the antidepressant utility of D22 in a genetically based animal model of depression, the Flinders Sensitive Line (FSL) rat. Importantly, like humans, FSL rats show reduced depressive behaviors after repeated but not acute antidepressant administration. Thus, the FSL rat model can be used to identify novel drugs, or drug combinations, that may have faster acting antidepressant‐like activity and improved therapeutic efficacy.MethodsAntidepressant‐like behaviors were assessed in adult, male Sprague Dawley (SD) and FSL rats using the forced swim test (FST). Rats were tested 30 min after single saline, fluvoxamine or D22 injections given intraperitoneally. Uptake 2 transporter expression was measured by western blotting techniques and radioligand binding of [3H]D22 in rat hippocampal preparations.ResultsAs expected, FSL rats displayed higher baseline levels of immobility in the FST indicating a higher level of depressive behavior compared with SD control rats. Also, as expected, acute injection of the SSRI fluvoxamine (10 mg/kg) reduced immobility time in SD but not FSL rats. Conversely, acute D22 (0.1 mg/kg) administration significantly lowered immobility time in FSL rats, but was not effective in control SD rats. FSL rats also appeared to have elevated expression of hippocampal OCT3 and PMAT total protein measured by western blotting. Measurements of uptake 2 transporter levels via D22 binding are currently in progress.ConclusionsThe reduction in immobility time observed after acute, low dose D22 in FSL rats suggests that OCTs and/or PMAT may be targets for rapidly acting antidepressant drugs, and underscores the utility of animal models for depression. Studies are underway to compare chronic D22 treatment with and without an SSRI in the FSL rat model of depression, with the goal to examine OCT3 and PMAT as targets to develop more efficacious and rapidly acting antidepressants.Support or Funding InformationNIH MH093320 and NRSA T32DA031115.
Characterization of the discriminative stimulus effects of lorcaserin in rats
Authors: Serafine Katherine M. , France Charles P. 
Published: November 2023

Several decades of preclinical research suggest that drugs with agonist effects at serotonin (5‐HT)2C receptors might be useful for treating substance use disorders. Lorcaserin, a drug currently used to treat obesity and under consideration for treating substance use disorders, has agonist properties at 5‐HT2C receptors; however, recent evidence suggests that it might also have agonist effects at other 5‐HT receptor subtypes. The present experiment used drug discrimination, a procedure that is highly pharmacologically selective, to further investigate the mechanism(s) of action of lorcaserin. Male Sprague‐Dawley rats (n=7) discriminated 0.56 mg/kg i.p. lorcaserin from saline while responding under a fixed ratio 5 schedule of food presentation. Lorcaserin (0.178–1.0 mg/kg) dose‐dependently increased lorcaserin‐lever responding. Several direct‐acting 5‐HT receptor agonists and antagonists were examined alone and in combination with lorcaserin. The 5‐HT2C receptor agonist mCPP occasioned greater than 90% lorcaserin‐lever responding in 6/7 rats, as did the 5‐HT2A receptor agonist DOM. The 5‐HT1A receptor agonist 8‐OH‐DPAT occasioned greater than 90% lorcaserin‐lever responding in only 4/7 rats. The 5‐HT2C receptor selective antagonist SB 242084 attenuated lorcaserin‐lever responding in all 7 rats. In contrast, the 5‐HT2A receptor selective antagonist MDL 100907 attenuated lorcaserin‐lever responding in 5/7 rats. In addition to producing directly observable behavior consistent with agonist properties at 5‐HT2C receptors (i.e. yawning), at large doses lorcaserin also induces behavioral effects that are consistent with agonist properties at 5‐HT1A receptors (i.e., forepaw treading). Moreover, when examined in combination with a selective 5‐HT2C receptor antagonist lorcaserin also induced behavior consistent with agonist properties at 5‐HT2A receptors (i.e., head twitching). Taken together, these results suggest that in addition to agonist effects at 5‐HT2C receptors, lorcaserin also has agonist effects at 5‐HT2A and 5‐HT1A receptors. Given that 5‐HT2A receptor agonists can be abused (e.g., LSD) it is crucial to fully understand the behavioral effects of lorcaserin if it is to be considered a potential pharmacotherapy for substance use disorders.Support or Funding InformationSupported by NIH Grants K05 DA017918 and T32 DA031115.
THE HEPATOPROTECTIVE EFFECTS OF WHOLE PLANT EXTRACTS OF OCIMUM BASILICUM IN EXPERIMENTALLY INDUCED LIVER DAMAGE IN RATS
Authors: Abatan Matthew Oluwole , Asala Margeret Titilayo 
Published: November 2023

The liver plays a central role in the metabolism of various endogenous and exogenous substances. This therefore exposes the liver to all kinds of insults produced by many materials including drugs, plants, domestic and industrial chemicals. More than 900 drugs have been implicated with liver injury. There are few medications mentioned to have ameliorating effects on liver damage. However some medicinal plants are reported to have hepatoprotective effects on liver damage.Ocimum basilicum of the plant family Lamiaceae is widely cultivated as a nourishing food and traditionally used as an antispasmodic, aromatic, digestive, carminative, stomachic, antinephrotoxic and tonic agent. This study was conducted to evaluate the antioxidant and hepatoprotective activity of Ocimum basilicum whole plant extracts using acetaminophen induced liver damage in rats as an experimental procedure using silymarin (100mg/kg) as a reference agent.Dried homogenized whole plant of O. basilicum was subjected to gradient extraction using chloroform, diethyl ether, ethyl acetate and methanol and the extracts obtained from these tested for hepatoprotective activity by pre‐treating groups of rats with different dosages for 7days before inducing liver damage with acetaminophen at 750mg/kg on the eight day. Liver function test was conducted by determining levels of serum liver enzymes as aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), total bilirubin, blood urea nitrogen (BUN), total protein and histological studies. The solvent extract with the highest bioactivity was further subject to vacuum liquid chromatography (VLC) and the fractions assayed for their antioxidant properties using DPPH radical scavenging and the ferric reducing antioxidant power assay (FRAP) procedures with ascorbic acid as standard.Results showed that all the solvent extracts significantly reduced (P<0.05) the levels of the serum enzymes AST, ALT, and ALP with significant reduction (P<0.05) also in BUN, total protein and total bilirubin when compared with silymarin. However the highest reduction was seen with the methanol extract with the experimental rats manifesting only few histopathological changes in their liver compared with those of the rats pre‐treated with the other solvents. The VLC fractions from the methanolic extract produced significant DPPH and FRAP activities when compared with that of ascorbic acid.The results of the studies suggest that the plant Osimum basilicum may have hepatoprotective with antioxidant activities and supports the folkloric medicinal use of the plant in handling some diseases.
Endogenous Substrates for Tumor‐Specific Human Cytochrome P450 CYP2W1
Authors: Zhao Yan , de Montellano Paul Ortiz 
Published: November 2023

Human cytochrome P450 enzymes play an important role in the metabolism of steroids, vitamins, eicosanoids, fatty acids and xenobiotics. CYP2W1 is a recently‐discovered human cytochrome P450 enzyme with low or undetectable expression in both adult human liver tissues and extrahepatic tissues, but high expression in human fetal tissues and in many tumor samples, especially colon and adrenal tumors. The distinctive expression pattern of CYP2W1, which features high expression in fetal and tumor tissues, but no expression in normal adult tissues, suggests that the cancer‐specific expression of CYP2W1 might be related to reversion to more primitive, embryonic cell types in which it had specific physiological roles.In this study we explored the physiological function of CYP2W1 in fetal development and cancer progression by searching for its endogenous substrates. We identified seven endogenous ligands that exhibited binding affinities to CYP2W1: retinoic acid, retinol, retinal, arachidonic acid, farnesol, geranylgeraniol and 17β‐estradiol. CYP2W1 exhibited tight binding affinities for retinoids, which have low nanomolar binding constants, and much poorer binding constants in the micromolar range for the other four ligands. CYP2W1 readily converted all‐trans retinoic acid (atRA) to 4‐hydroxy atRA, all‐trans retinol to 4‐OH all‐trans retinol, and also readily oxidized retinal. The enzyme much less efficiently oxidized arachidonic acid to 8,9‐diHETrE, 11,12‐diHETrE and 14,15‐diHETrE, 17β‐estradiol to 2‐hydroxy‐(17β)‐estradiol, and farnesol to a monohydroxylated product. These findings indicate that CYP2W1 probably plays an important role in localized retinoid metabolism that may be intimately linked to its involvement in tumor development.Support or Funding InformationThis work was supported by NIH grant GM25515.
Chronopharmacology of cisplatin: Role of the circadian rhythm in modulating the cisplatin transporters levels
Authors: Sorensen Daniel N. , Dakup Panshak P. , Gaddameedhi Shobhan 
Published: November 2023

PurposeCisplatin is one of the most commonly used chemotherapeutic drugs in treating a variety of tumors including cancers of ovaries, testis, lungs, blood and solid tumors of the head and neck. However, the major limitation of cisplatin as a chemotherapeutic drug is due to tumor resistance and nephrotoxicity. The main focus of our project was to study the chronopharmacologic effects that have been demonstrated in human models of cisplatin chemotherapy showing decreased renal toxicity and side effects. We hypothesized a mechanistic, circadian rhythm‐based cause for these outcomes. To further evaluate our hypothesis, we have screened the expression levels of all known cisplatin transporters (both influx and efflux) as well as the cisplatin‐DNA repair activity as a function of the circadian rhythm.Experimental DesignStudies were done on mouse models of wild‐type and circadian disrupted Per1/2 −/− animals from tissues samples (kidney and liver) taken at different circadian time points and compared via qRT‐PCR analysis for RNA expression along with the same study with human blood samples by the time of day in a 24‐hour period. In case of cisplatin‐DNA repair activity as a function of the circadian rhythm, immuno‐slot blot assays were performed.ResultsData from kidney tissue RNA samples showed possible clock controlled transporter expression in wild‐type animals as compared to Per1/2 −/− including OCT2, MRP1 (GS‐X) and ATP7A. These mice showed higher expression during the evening hours compared to the morning hours. This was also seen in fresh samples of human blood where the expression levels of these transporters were in opposite phase to mouse tissues. In addition to the circadian variation on expression levels of the above transporters, our findings suggest that cisplatin‐DNA repair function might also be regulated by the time of day in mouse kidney.ConclusionsThese findings indicate a possible mechanism for the chronopharmacology of cisplatin in minimizing the toxicity associated with it and reveal a target for future study of additional mechanistic causes of circadian dosing changes in cisplatin and other medications.Support or Funding InformationWSU College of Pharmacy Start‐up Funds
SAABFAT6‐induced anti‐growth and survival of A549 adenocarcenoma cell is mediated via death and survival pathways and downstream cascades involving regulation of NF‐κB expression
Authors: Kwende Syntia , Oyagbemi Ademola A. , Fagbohun Olusegun A , Omobowale Olutayo T , Adedapo Adeolu A , Yakubu Momoh A 
Published: November 2023

We have examined the mechanism of SAABFAT6‐induced antiproliferation and cytotoxic effects on A549 adenocarcenoma cell line. Ethanol extracts of SAABFAT6 (0.5–2 mg/mL) was incubated with A549 cell line and in vitro in the presence or absence of PTK/PKC activator or inhibitor (Ang II, PMA, Tyrphostin, or Calphostin C). Effects of treatments on proliferative/cytotoxic activities or protein expression were evaluated using MTT assay or western blot analysis. SAABFAT6 significantly attenuated A549 cell proliferation at 48 (47%) and 72 (68%) but not at 24 hrs (0.5 mg/mL) and reducing cell growth by ~76% at all‐time points for 1 and 2 mg/mL. For cytotoxic effects, incubation of A549 with SAABFAT6 significantly reduced cell survival by 72%, 86% at 48 and 72 hrs for 1 and 2 mg/mL SAABFAT6 significantly reduction cell survival by 45, 72, and 89% at 24, 48 and 72 hrs, respectively. These effects of SAABFAT6 on A549 growth and survival were potentiated by activator as well as inhibitor of PTK/PKC while significantly attenuating NF‐kB protein expression. We hypothesize that SAABFAT6 is probably acting by interfering with cellular signaling proteins associated with death and survival pathways (PKT/PKC/MAPK) and probably via downstream cascades involving regulation of NF‐κB. Our data may help to identify the most important target molecules for the antiproliferative and cytotoxic actions of SAABFAT6; serve as a novel drug‐supplement in chemotherapeutic regime against adenocarcenoma useful in the prevention and management of lung cancer growth and resistance. Further researches are required to further identify pathway specific mechanisms of SAABFAT6 actions.Support or Funding InformationCarnegie African Diaspora Fellowship (IIE Grantee ID: 15410197)
Natriuretic Peptide Receptor‐C Agonist Attenuates the Enhanced Expression of Gqα, PLCβ1 Proteins and Vascular Smooth Muscle Cell Hypertrophy From Spontaneously Hypertensive Rats: Role of ROS and ROS‐Mediated Signalling
Authors: Jain Ashish , Anand‐Srivastava Madhu B 
Published: November 2023

Hypertension is associated with vascular remodelling due to hyper‐proliferation and hypertrophy of vascular smooth muscle cells (VSMCs). We earlier showed the implication of enhanced expression of Gqα and PLCβ1 proteins in VSMCs from 16‐week‐old spontaneously hypertensive rats (SHR). The present study was undertaken to investigate whether C‐ANP4–23, a natriuretic peptide receptor‐C (NPR‐C) agonist that has been shown to inhibit vasoactive peptide‐induced enhanced protein synthesis in VSMCs, could attenuate VSMC hypertrophy in rat models of cardiac hypertrophy and to explore the underlying mechanisms contributing to this inhibition. For these studies, aortic VSMCs from 16‐week‐old SHR were used. The protein synthesis, a marker of hypertrophy, was determined by (3H) leucine incorporation and the expression of proteins was determined by Western blotting. The protein synthesis was significantly enhanced in VSMC from SHR as compared to WKY and C‐ANP4–23 treatment attenuated the enhanced protein synthesis to WKY control levels. In addition, the enhanced expression of Gqα and PLCβ1 proteins in VSMC's from SHR was attenuated by C‐ANP4–23 treatment. Furthermore, C‐ANP4–23 also attenuated the enhanced levels of superoxide anion (O2−), NADPH oxidase activity, the increased expression of NOX4, p47phox and p22phox, as well as the enhanced phosphorylation of ERK1/2, AKT1/2 and c‐Src. In conclusion, these results indicate that C‐ANP4–23, via the activation of NPR‐C, attenuates VSMC hypertrophy through its ability to decrease the over‐expression of Gqα, PLCβ1 proteins, enhanced oxidative stress and MAPK/AKT signalling pathway. Thus, it can be suggested that C‐ANP4–23, an activator of NPR‐C, may be used as a therapeutic agent for the treatment of vascular complications associated with hypertension and atherosclerosisSupport or Funding InformationSupported by grants from Canadian Institutes of Health Research and Heart and Stroke Foundation of Canada.
Impaired Vascular Contractility to Uridine Adenosine Tetraphosphate (Up4A) in Angiotensin (Ang) II‐Induced Hypertensive Mice: The Receptor Desensitization?
Authors: Zhou Zhichao , Yadav Vishal R , Sun Changyan , Teng Bunyun , Mustafa S. Jamal 
Published: November 2023

We previously showed (Zhou et. al., Vascular Pharmacol. 73:78–85, 2015) that Up4A‐mediated vascular contraction is partly through purinergic P2X1 receptors (P2X1R). Since the plasma level of Up4A is elevated in hypertensives, which implies a crucial role for Up4A‐P2X1R signalling in hypertension. We investigated the vasoactive effect of Up4A in Ang II‐infused mice. Mean arterial blood pressure (MAP) was measured daily in saline or Ang II‐infused mice. Aortas were isolated for isometric tension measurement. Protein expression of Ang II type 1 receptor (AT1) and P2X1R was assessed by Western blot. MAP was elevated by ~50% in 3‐week Ang II‐infused mice indicating hypertension. Protein levels of both AT1 and P2X1R were upregulated in Ang II‐infused aortas. Surprisingly, Up4A (10−9–10−5 M)‐induced concentration‐dependent contraction in saline‐infused aortas was significantly impaired in Ang II group. Both P2X1R antagonist MRS2159 and AT1 antagonist losartan attenuated Up4A‐induced aortic contraction in WT. However, Up4A‐induced aortic contraction with AT1 desensitization by the prior Ang II (100 nM) stimulation in WT was similar to that without the Ang II stimulation, while the second Up4A‐induced aortic contraction was markedly reduced as compared to the first exposure in the same preparation, suggesting a desensitization of P2R. This desensitization was further confirmed by P2X1R desensitizer α, β‐methylene ATP (10 μM). In conclusion, despite the upregulation of AT1 and P2X1R in hypertension, Up4A‐mediated aortic contraction was impaired in Ang II‐infused mice, which was likely through the desensitization of P2X1R but not AT1. This study implies that vascular P2R activity rather than plasma Up4A level may determine the role of Up4A in hypertension.Support or Funding InformationSupported by HL02339, HL094447 from NIH and MEPSCKL201301 from Sichuan Medical University
Pharmacological evidence that NaHS inhibits the vasopressor responses induced by stimulation of the preganglionic sympathetic outflow in pithed rats
Authors: Sanchez‐Lopez Araceli , De La Cruz Saul Huerta , Gutierrez‐Lara Erika J , Beltran‐Ornelas Jesus H , Centurion David 
Published: November 2023

It has been reported that i.v. administration of NaHS, a donor of H2S, elicited dose‐dependent hypotension although the mechanisms are not completely understood. In this regard, several mechanisms could be involved including the inhibition of the vasopressor sympathetic outflow. Thus, this study was designed to determine the potential capability of NaHS to mediate inhibition of the vasopressor responses induced by preganglionic sympathetic stimulation. For this purpose, Wistar rats were anaesthetised, pithed and cannulated for drug administration. In animals pre‐treated with gallamine, the effect of i.v. infusion of NaHS (310 and 560 μg Kg−1 min−1) or its vehicle (phosphate buffer) was determined on the vasopressor responses induced by: (1) sympathetic stimulation (0.03–10 Hz); (2) i.v. bolus injections of exogenous noradrenaline (0.03–3 μg Kg−1); or (3) methoxamine (1–100 μg Kg−1). The vasopressor responses induced by preganglionic sympathetic stimulation were dramatically and dose‐dependently inhibited by i.v. infusion of NaHS (310 and 560 μg Kg−1 min−1), but not by vehicle, particularly at high frequencies. In marked contrast, the vasopressor responses to exogenous noradrenaline or methoxamine were not inhibited by the above doses of NaHS or its vehicle. The above results, taken together, demonstrate that NaHS inhibited the vasopressor responses induced by preganglionic sympathetic outflow by a prejunctional mechanism. This is the first evidence demonstrating this effect by NaHS and may contribute, at least in part, to the hypotension induced by NaHS.Support or Funding InformationThe authors acknowledge to Conacyt for their financial support.